Convoy S2+ new firmware (biscotti) memory mode jammed

Thanks. Can be used as hand warmer on max. :slight_smile:

Concerning the above Biscotti instructions crib sheet, with mode memory on it reads “enter into next mode”. Seriously? The dreaded next mode memory? Wouldn't it make a lot more sense if it were “enter into current/last used mode”?

Simon announced availability of SST40 drivers with Biscotti “coming soon”, by the way.

Hi Barkuti,

When I have memory mode on for my Convoy Biscotti lights it always comes back in the last mode it was on before it turned off.

I would agree that if it came back on in the next mode it would be annoying, but it does not appear to work that way thankfully.

I’m trying to decide which flashlight I should buy, so last couple of days I’m reading tons of reviews about two specific flashlights for EDC. One possible pick is Convoy S2+ (with orange peel, for flood). So I’m reading what ppl are saying trying to find out the bad things about flashlights I have in my focus.

So, about this firmware issue… I have a question:

I own a MiniPro TL866A programmer. It came with tons of adapters, so I guess the ‘refleshing’ the ‘new’ firmware (if I pick convoy S2+ and get a bad firmware) would be possible with MiniPro TL866A ?
What kind of package is the IC that holds the firmware? And where to find the latest firmware for ‘refleshing’?

You also mantioned ‘gchart’s Babka’. I guess thats another firmware developer for S2+? Where to find his firmware and is it better they better? (I’m gessing…. at github?)

Another (probably kinda) offtopic question: I want a flashlight with orange peel reflector, but I’ve noticed thats S2+ with orange peel reflector comes with 2 group modes, not like others with ‘smooth reflector’ which comes with 12 group modes. Can I get an S2+ with orange peel and latest (bug free) 12 group modes?

Thanks for your answer!

twist3r, Simon the manager from the Convoy store will readily change whatever smooth reflector in your S2+ order to orange peel with ease. He in fact can customize whatever order by ordering first the base flashlight and selecting “other payment methods” (you may need to use the AliExpress application, add to the cart then proceed to see the other payment methods option), then postponing the payment. That way you can message him with whatever custom changes required, and he will later adjust the final price for you to pay. You can also tell him that you're a BLF user, and for it he will make you a discount if you will. :-)

Wed, 02/05/2020 - 05:43

If ordering direct from the official Convoy AliExpress store, you can send a message to Simon (the owner of Convoy), to configure what you need.
So you could ask him to get you a Convoy S2+ with XM-L2 with OP reflector (this is the default anyway), then you could specify Biscotti (12 group modes) with 7135x3 if that’s your preferred configuration.

Unfortunately regarding the “buggy” thing, I’m not very certain what causes that to happen, I have had it happen on some people who asked me to check their flashlights (getting stuck). I have also tried changing the buggy Biscotti driver on a Convoy C8+ to a new (not-yet-buggy) Biscotti driver, as the driver board on Convoy C8+ requires minimal soldering only (I’m very poor at soldering or maybe I don’t have a good soldering iron… — I have not been able to unsolder a 7135x8 driver from a Convoy S2+ head “pill” after several tries, for instance…).

Thanks for your reply Barkuti. Currently I’m gathering so much information that I think its better if I slow down a bit, cause my brain is getting stuck like that biscotti memory mode. :slight_smile:

I’m new here, and I’m trying not to bother too many people. Still, I have to ask questions because I’m about to order my first ‘smart’ flashlight. What I would like is a flashligth with flood light and with that kind of light that can ‘flood’ the area in front of me (from my feet up to 3-5m, max 10m away without ugly hotsopt light). If it can ‘throw’ light in the distance, thats a plus. Also I was trying to pick 7135x3 because I wanted the flashlight not to get hot too fast and the battery to last longer, but I wasn’t thinking that 7135x3 would give less lumens compared to 7135x8. Can someone tell me if I’m correct:

If Cree XML2 gives… 1040lm and I pick 7135x8 but use it at 10% mode, that will give…~ 104lm and the flashlight wont get hot too fast and battery will last longer, with light enought to clearly see whats in front of me, without hotspot light (if I pick orange peel)?

I’m also thinking if I should order 5 extra different led lens here:
…and use 60 degree one. Will that ‘improve’ the flood and remove hotspot?

Can someone help, please? (I’m sorry for making an offtopic post here)


d_t_a thanks for your reply too. I will see if I can contact Simon once I finally decide what I really want. Isn’t he a member here, maybe?

One extra question (probably st*pid one but I have to ask): if I pick 7135x8 …I can still order later 7135x3 and switch it? Or…not?

I edited my last message and reworded my last sentence in it, there you have it.

When you say you want ‘flood’ without ugly hotspot, and if it can throw in the distance that's a plus, you seem to be asking for a zoom flashlight. Zoom flashlights, with aspheric lens, lose some amount of out the front light when in flood mode (with the lens closest to the emitter), and as you “zoom out” the lens gets farther away from the emitter resulting in a lesser extraction of emitter light but tighter hotspot. But let's avoid being dramatic with the emitter light extraction thing, zoomie flashlights produce excellent and uniform “blankets of light”, being very adaptable (I often every day carry -EDC- one of them). The thread Zooming Model List (2018 Updated) Tell us about your newest zoomie! is a better place to get information on these matters.

A TIR lens will net you a nice blanket of light for close up illumination, with smaller angles being more throwy. I often use an S2+ clone with a 30° TIR lens for close up work (tip: use BLF coupon at FastTech).

Orange peel reflectors give better beam profiles than smooth ones, namely concerning seamless transitions from hotspot to corona and spill (without rings or other possible artifacts even with multi-die emitters). You will still have a hotspot, though.

Last question is a yes, that is a driver swap. If never done you'll need to get skilled on making very flat wire solder joints on emitter MCPCBs, this is because reflectors often sit quite close to them and you don't want to cause electrical shorts (get and use some “kapton” tape just in case).

Thanks Barkuti for your reply.

The reason why I said that if the flashlight ‘can throw in the distance that’s a plus’, is only to make it clear that I want a flood (orange peel reflector type of) flashlight. Ofcorse every flashlirght throw light, but those with smooth reflector can throw further. I mostly need flashlight that will light up the area around me (in front of me) and 3-5 meters ahead, with 10 meters being max that I’m interested in. Everything ahead of that is a ‘plus’ (thats why I said what I said, not because I really need it).

Now, the next information is not important, but I want to explain for what ‘situation’ I would mostly use this kind of flashlight: For ‘flea market’. At the ones in my area, sellers comming before sunrise (which means its still dark or ‘night’), and lots of them already started selling their staff. So I need a flashlight for that kind of situation. To light up the area in front of me (up to 3-5 meters, to 10m being max). Thats what I’m interested in. So I can see what the sellers are offering, and also without being destracted by a hotspot. For that, since I’m an newbie, I would guess 50lm (or 150lm) would be enough to clearly see whats in front of me, and at the same time not waste much battery and not make the flashlight ‘hot’. I guess 40% mode or 30% (of an 7135x3 6T-3B XML2 )would be good for that.

I also read at CPF topic created by Phlogiston (he is a member here as well, but I don’t see that he made the same thread), about Convoy Lights: Option Comparison Tables and Images. I’m not sure that I’m alowed to post links to external sites, so I will not do that but simple google search will find it as a top 1 result. In his topic he posted a tables where he compared some 7135x3 with activated modes like 5–40–100% and he was getting “21 lm —160 lm — 370 lm” for Convoy S2+ Red XML2 T6-3B LED 7135*3 driver. The issue here for me is that I’m a newbie, so I don’t know exactly how many lumens actually looks like in the real life. Is it ~25 enough, maybe 40-50lm ? Or maybe 160lm for what I need? (that flea market ‘thing’).

As for soldering (driver swap), well… I’m not good at soldering yet, though I would like to think that I own an ‘ok’ soldering iron (HAKKO FX-888D). Skill is what I lack. :frowning:
Since you mantioned ‘kapton tape’ I guess that maybe desoldering requires ‘hot air blower’ instead of solder iron?

Again, thanks for your reply and I apologise for making another offtopic post.

I read more and I’m kinda getting close (at least I want to believe) to what I might decide to ask Simon to make for me for S2+ (if he wants):

Color: Desert tan (Sand)
Driver: 7135*3
Emitter: XML2
Emitter BIN: T6-3B
Light temperature: 5000-5200K
Reflector: Orange peel
Switch Type: metallic clicky switch (‘black metallic clicky’)
Mode memory: Yes

firmware: ?
(I need to decide if I want new firmware depending how much lumens in real life at 5-10% and 30-35-40% an 7135x3 Driver can produce. Old firmware had 2 group modes with 5-40-100% (custom mode was possible with 5-30-100), while new firmware gives modes with 1-10-35-100 (group #10). So I have to think/decide about what is the actual difference between 5-10% and 30-35-40% when in comes to light that I would get in front of me or 3-5 meters away)

modes: ?
(modes depend if I will go with old default/custom firware or with new firmware which has 12 mode groups (#10 being the one I’m interested in)

^ those are my thoughts for now. It’s hard to decide but I hope that I’m close to narrow down my final pick.

If you guys have any thoughts/suggestions I’ll be happy to read it. Thanks!

twist3r, I mentioned kapton tape because, when replacing a driver, you will need to desolder the old driver wires from the emitter's MCPCB, leaving the MCPCB pads more or less clean from solder. You will then solder the new driver wires to the MCPCB pads making sure they are remain pretty flat, without bulges. If after this operation you place the reflector over the centering ring/gasket and it touches the solder joints on the pads, you know that needs a fix. If it passes the test, place a couple small pieces of kapton tape over the solder joints to be sure it'll remain short-circuit safe, it's for insulation purposes. Other tapes may also work, but kapton is neat and heat resistant.

If I were you, for a flea market before sunrise, I would select a high CRI emitter of low to moderate temperature (2700K - 4000K). This is just an opinion, of course, but for close up work I prefer light quality. Also, lower emitter tempeatures will respect more your night vision.

If you go with a 3x 7135 driver you'll end up using it in high most of the time. The flashlight won't get hot with such power. You could get an 8x 7135 driver and use it in some medium mode, but it won't be as energy efficient. I don't really like 7135 drivers because of PWM in medium and lower modes, the efficiency advantage of the lower modes gets negated by PWM (this translates into slightly less output); and while most people don't complain PWM can be disturbing to some. For a 7135 driver, I would get one with 4x 7135s and always use it in high; the emitter would get 1.4 A (without PWM), the flashlight wouldn't get too, and you would get a nice deal of out the front light (300 - 500+ lumens depending on emitter and reflector/lens type).

Personally I would go with some (CRI95+ 2700K or 4000K) SST-20 emitter, and one of the newer ∅17mm 4-mode SST-40 linear drivers with temperature control (very nice medium mode at nearly 1.5 A effective, and you have the extra power of a high mode on demand). Simon said he is working on Biscotti for the newer drivers, by the way. The reflector won't be so neat at very close distances, or you may like it. In any case replacing the reflector/lens is easy so grab at least a 25° TIR, I'm sure Simon can ship you some additional lenses with your flashlight for a few extra bucks. Since you don't know which reflector or lens type will fit you best yet, you'll thank this later.

P.S.: I find myself comfortable using my S2+ clone in medium mode (0.9 - 1 A) with a 30° TIR, lighting 3 - 4 meters in front of me.

I would get a 7135*8

you can configure it in one of the 12 groups to put out 50% max and pretend you have a 7135*4 or however that works…

You can unlock a new mode later for moar power…
You can never do that if you are stuck with the 7135*3…………

Barkuti thanks a lot for trying to help!

I’ll be honest. I know you did your best to help me. You gave me lot of examples what would you do. But… now I’m more confused than what I was before. :frowning:

My biggest issue is that I don’t know how (in real life) certain amount of lumens are good for me (for what I want to use flashlight for, in this case ‘before sunrise flea market’).

I need flashlight to:
-last long
-don’t get hot
-have flood (I think I need ‘flood’ because, in my head, I think ‘flood’ with equally light up the whole ‘area’ in front of one seller, but maybe I’m wrong because it will give less ‘lumens’)
-to not have hotsopt circle ring (if possible)

^ one more explanation why I think it would be good to have a ‘flood’ type of flashlight is, when I come in front of a seller’s staff, if I use ‘thrower’ it will be like snipping some item which would ‘tell’ the seller I might be interested in a specific item (which I don’t want to reveal to him so easily because I want to bargain with him about the price, but not let him know I ‘really’ want it, if you know what I mean) :slight_smile: So ‘flood’ light would show me all his items, but not ‘directly’ point to a specific one so fast.

I was at flea market last Sunday, and I did noticed some people with ‘strong’ lamps. I’m sure some of them bought Convoy or simmilar ‘smart’ flashlight, but I knew about all this much less than now, and even if I tried to ask them about ‘what type’ of driver, emitter, or emitter bin their flashlight was using, I guess some of them woudn’t have time to bother with details, some probably wouldn’t even know, and some wont tell). I only noticed (if I remember correctly) that probably 2 out of 3 guys had lamps with that snipping hotspot circle ring. They also were switching off their flashlights so fast, which is what I don’t want to be forced to do. (I guess if they were using 7135*8, they didn’t wanted a lamp to get hor too fast, or to waste battery so fast).

justanotherguy, thanks for your answer!

Yes, I understand what you’re saying, BUT… even if I use 7135*8 at 50%, woudn’t that also (still) force the battery to lose power faster and to get hot faster?

One more thing that I read (post is 3 years old now) is that Convoy S2+ (at the time) didn’t had low voltage cutoff but only low voltage warning. It said that Toykeeper made a new firmware version (probably biscotti) but it was only for Convoy C8 at the time. Is it possible to get such option within the firmware that flashlight comes with? (trying to think about protection as much as I can)

0K. First of all, even if you care to use a warm high CRI emitter like a 3000K CRI80+ XM-L2 or 2700K/4000K CRI95 SST-20, you should get more or less 300+ lumens out the front of the flashlight with a TIR lens if the emitter is driven at 1.4 - 1.5 A (check some emitter reviews like Test of a Luminus SST-20-W 3000K 95CRI led -djozz- or Luminus SST-20-W 4000 K CRI95 color and output test -maukka- if you like). I'm already counting some optic and heat losses, but my figure should be close enough. The TIR lenses will provide you with a nice blanket of light (no hotspot at all), so no one will think you're "sniping" something unless you straight focus at it leaving it in the center of your beam. My close up work flashlight has a 30° TIR, and to my eyes it covers a 60° angle (the figure is a half angle metric). So ask Simon to bundle you at least 2 or 3 lenses (10°, 25° and 45°), or just order a "1pcs per degree" 5-pack (10°, 25°, 45°, 60° and :???: strip lens), that way you'll be able to test by yourself which ones you like better. A lens with a wider angle will spread out the light more, making the beam less intense and you may have to get closer, but at the same time you'll cover a wider area and be able to peek more items stealthily.

As I said above, you can get the SST-40 driver which goes up to 5 A or some Biscotti 8x 7135 driver both of which, in medium mode, will provide you with decent light. The SST-40 driver will give you almost 1.5 A in medium -30%-, while an 8x 7135 in medium mode will be somewhat below depending on the chosen mode group, so it'll be less bright. With 1.5 A at the emitter, a 3000+ mAh cell and a low Vf emitter, you'll at least have 2 hours of non-stop runtime, a little bit more in practice depending on the cell you use. Don't worry with the temperature thing, 1.5 A max means 5 - 6 W of burnt power at the flashlight, it doesn't gets too hot at that power (and anyway, the SST-40 driver has temperature control). I once used my nephew's S2+ with a headband to go jogging (40+ minutes, an after repair test) at night, and it performed wonderfully without getting toasted.

Runtime speaking you can switch modes to save power, and/or take more batteries with you if needed; it's a pretty quick swap.

Thanks Barkuti for your reply.

I saw your message about 10 days ago when you posted it, I just didn’t know exactly what to ask next, even though I felt like there is something that I still don’t understand. So I let the time pass, while trying to figureout whats that thing which still makes me confused.

First, since I’m still new to all this, I didn’t knew what CRI means. So I googled it and watched some YoutTube clips. If I understood correctly, CRI represent how good specific led diode can show the difference between different colors (they used 8 colors in some youtube examples). So in theory, CRI 100 is a perfect one. In other words, higher the CRI, better the led diode is. Correct?

I see that you said for XM-L2 it is CRI80+. Can’t that CRI value be more specific? For SST-20 you said its CRI95. From what I understand a diode with CRI95 should be good at showing the difference between colors, right?

2nd question: You suggested using ‘warm’ high CRI emitter (3000K or 2700K/4000K). When I was looking at the sales page of Convoy S2+ with XM-L2 emitter I saw that Convoy is offering couple different eminter bins to choose from:

XML2 U2-1A 6500-7000K
XML2 T6-3B 5000-5200K
XML2 T6-4C 4300-4500K
XML2 T5-5B 4000-4200K
XML2 T4-7A 3000-3200K

^ (btw whats the difference between ‘bins’ and ‘tints’ terms?)

Since there are photos attached at the same sales page, I decided that I most like how 5000-5200K appears (or ‘neutral light’). Maybe ‘4300-4500K’ (which should be ‘neutral-warm light) could be ’ok’, though its starts looking yellowish compared to 5000-5200K. But, anyway, what confused me is that you’re suggested ‘warm high CRI emitter’ of 3000K (or 2700K/4000K). Will that makes the light even more yellowish? Why not higher ‘K’ value (like the one for ‘neutral white’ 5000-5200K)? Does SST even have emitters ‘that high’?
Also, while I was trying to figureout why you suggested lower ‘K’ value, I thought maybe because it will not waste battery fast (since the light wont be as bright compared to 5000-5200K). Correct?

To make myself even more confused, couple of days ago it was some rainy weather in my area. I was walking the street after the rain and I come under those high (15-20 meters above the ground) street light. They were dropping yellow light (like the ones for ‘foggy’ weather), and the light was somehow ‘nice’ to look at. But then again, who knows how powerfull are those street lights (and probably not even using LED, but probably some ‘older’ technology). So I was like ‘huh’.

Another thing to mantion is… I saw someone using those foggy yellowish flashlight at flea market, and…they kinda looked like… (tooo dimmed), because everywhere around were those guys with high (neutral-white or cool-white) flashlight, and when their flashlight overlap the yellowish light from other people, you just see the difference and after the ‘high light’ guys move away, and you stay starring at that yellowish light, you kinda feel like you are left in the dark, if you understand what I mean.

Third question (this is a st*pid one): If 7135*8 and SST-40 are the drivers. What is biscotti? A firmware? Or ‘software’ ? You said Simon is working on biscotti for new drivers, so I guess you were suggesting I could pick SST-40 driver and ask simmon that it comes with biscotti? I hope I understood this well…

Fourth question (probably another st*pid one): In one of your previous posts, you said that SST-40 linear drivers have temperature control. I’m guessing its for protecting the battery from overheating? What if… temperature control fails? I know that I’m paranoid but… ofc I don’t want things to explode while in my hands. (though you said the lamp wont be warm if I use it at 30% (middle range)). I Guess if I use it at 100% with 5A current it will make everything supper bright and at the same time supper hot very fast?

Another thing that I read somewhere (someone posted it, maybe it was from amazon sales page, I really don’t remember) is that the lamp that he bought with dimming feature (which is what software do when your battery starts to drop voltage, I guess?) …he said ‘after a month dimming stopped working’. How that can be possible? And is the percentage of such ‘failures’ pretty high or low, in your oppinion? Don’t want to get in situation where I would buy a lamp and then because of software or (bad component) I’m left in the dark.

btw. does that SST-40 driver has an option to shut down the flashlight if the voltage drops at…lets say 2.9v or 2.8v ?

Another question: When it comes to emitter bins, there are tons of them, for instance: U2-1A, T6-3B, T6-4C, T5-5B, T4-7A. In this topic: Warmest tint for each bin there was an image posted. This one:

When I look at that image I can find 3B (from T6-3B emmiter), but what does T6 represent? (what are those U2, T6, T5, T4 ?) What are they?

2 offtopic requests/questions:

1. can you post (image or YT clip) how that flashlight from your nephew looks like? Or better, if you have that High CRI95+ SST-20 with SST-40 driver, can you please post picture/clip so I can see how that looks like?

2. You suggested Li-Ion rechareable 3000mAh battery. Which model (and brand, of those 5 major ones) should I buy? And is it correct to take protected one over ‘unprotected one’? I kinda want to secure myself as much as I can. (I’m guessing order from should be a good choice to buy from?)

Thanks in advance for your answer and sorry for this flood of questions.


I just checked site and (ofc) I got one more extra question: if SST-40 can take 5A, is buying a battery with 6.7A discarge current enough for that driver?
I mean this one: Panasonic NCR18650B 3350mAh - 6.7A

Also, what you think about these two:

Samsung INR18650-30Q 3000mAh - 15A
Samsung INR18650-35E 3450mAh - 10A

^ among reviews at site for those batteries, someone mantioned that he is a BLF member and that he bought 300 pcs already and is happy with it. So, I’m guessing they are good. Though all unprotected one. (not sure if ‘unprotected’ is what I want in my hands)

Just checked this one: LG INR18650-M36 3600mAh - 5A and in the description it sais:

And when I sort the search (at nkon website) by those who has ‘protection’ I get results with not a single one major brand (of those 5 major ones) among them. Well… fck. :frowning:

First of all, the Wikipedia has a good definition for CRI. It's not the only method of color rendering evaluation, it just is the oldest (and the worst) but still valid. You can for example check “TM-30-15 vs. CRI and the Future of Color Rendering” and “TM-30-15: A New Method for Measuring Color Rendition” (there are further methods too).

As human beings we are adapted to natural light sources: the Sun, fires, and blackbody radiators namely. All these “ideal” light sources have spectral power distributions which allow the average human being to properly discern color information. Light sources whose spectral power distribution differs from ideal make stuff look “less appealing” to us. Here are a couple of videos on this subject:


Also let me say that an LED diode “isn't good at showing the difference among colors” because it's us who, in our minds via our eyes (senses), do that in response to a natural or ideal light source. Some people don't like or need high CRI leds because they are “less efficient”, but this also is rigged or tampered way of looking at the matter because perceived brightness obviously depends on our sensitivity to the different visible frequencies. I don't care about efficiency, those who care can buy some green led and have the best efficiency, at the price of super wrong color appreciation.

Bins and tints.-

Emitter bin is a measure of the relative output an emitter has at its binning current. Thus, the higher bin the higher the perceived brightness. Take a look at emitter datasheets for more information.

Tints are a way to classify an emitter's light output within the color space. Examples:

This is the way Cree does it, same graph as you posted above.

And here is how Samsung does around 4000K and below:

This graph is from LH351B emitter datasheet, hence the 350 mA binning current.

The photos attached at the sales page don't really look like “the real deal”. They may look “sort of”, but take it with a grain of salt.

The reason I suggest “warm” emitters is because it is easier on the eyes to use a warm light source at night. When at night our scotopic vision is active, this is one of the reasons “warm” (what you call “yellowish”) light sources look good. And it also is the reason why “n00bs” wandering with “cold white” flashlights can easily kill your night vision if they focus their flashlights to you directly, it has to do with the amount of emitted green-blue light from their leds. With a warm light source at night you can easily see in the dark without having to turn off the flashlight and waiting for your eyes/mind to adapt.

Yes, Luminus Devices also has emitters above 4000K; and no, lower temperature light sources won't waste battery any less.

The street lights you speak about probably are low pressure “sodium vapor” lamps (colors look like crap with them).

What you say on the topic of foggy yellowish flashlight versus neutral or cool white, hard to say without really knowing what they were using. I have warm flashlights whose output is a good deal higher than most standard neutral or cool ones lumen wise, but the main reason for the phenomena you describe probably is the higher “night vision killing index” of neutral or cool leds versus warm leds.

Biscotti is a microcontroller software for flashlights which Simon uses in his 7135 drivers. Simon said he was working on Biscotti for the newer “SST-40” drivers in his [Convoy] thread. It is also called firmware, as it is microcontroller software written in “low level” programming languages.

The temperature control in the SST-40 drivers prevent the driver (and hence the flashlight) from overheating by reducing the current on demand (55 °C max). In high (5 A) the flashlight would become hot quite fast without temperature protection. It can be disabled by removing the onboard NTC.

Different flashlights implement dimming modes differently, but it has nothing to do with reliability. The amazon sales page torch probably was of bad quality.

Can't really say for sure if the SST-40 driver will shut down the flashlight below a certain voltage, but I would bet on it. Anyway, even if it were not to do it, it is a linear driver; this means battery voltage would hardly drop below 2.5 V even if left on unattended for days (the minimum Vf of standard white leds is close to 2.5 V, this is the reason). Thus, it is safe anyway no matter if you use unprotected or protected batteries.

U2, T6, T5, T4… are emitter bins. They define a relative emitter output at some given current and temperature conditions.

My nephew's flashlight is a green S2+ I custom built from a host with Samsung LH351D 4000K CRI90+ emitter and ∅17mm SST-40 driver. Had it at home recently but forgot to take pictures, sorry.

NKON is a great place to buy cells.

The NCR18650B cell isn't bad, but I'd buy Sanyo NCR18650GA (refurbished units available), Samsung INR18650-35E or LG INR18650-MJ1 (available refurbished) instead.

The Samsung INR18650-30Q is a higher discharge cell. I'd get it for higher drain flashlights (7+ A), although it is a good choice anyway.

The LG M36 is good too (and it actually costs a bit less than the MJ1, wonder why as according to Henrik's tests its performance is about the same as its sibling.

Oh! I don't think you need a protected cell, but if you do, KeepPower does it good without asking too much money (nice example).

Next time one question at a time, I've spent a loong while with this LoL.

Wed, 02/19/2020 - 04:43

WOW! Thanks Barkuti!

Its a deal. :slight_smile:

I’m sure more questions will follow. Just finished reading your answer and I’ll need some time for my brain to process the new information that you just provided. Thanks!

Edited my post to add a small clarification as to why battery voltage is super unlikely to drop below 2.5 V, even if left in a flashlight with linear or unregulated driver without protection. Generally speaking only boost drivers can be problematic, but any decent boost driver has low voltage cut-off for li-ion cells.

Happy it is of service.

Wed, 02/19/2020 - 06:07

Thank you so much Barkuti, for all your explanations :+1:
Thank you so much twist3r, for asking the questions :+1:
Thanks everyone, for sharing your knowledge :+1:
every newbie like me needs to read this thread, a lot of good info here.

Nice it is of help, BLF-L. Had to fix the write up of my essay, by the way.

I just received the S2+ red LED and selected mode works for less than 30 seconds before it revert back to default, on / off at full.