Convoy S21A SFT40
At the end there will be a summary for those who like only particulars. In each topic I will bold the key sentences, so it will be easier to notice what's the most important. Enjoy!
This flashlight was provided by FlashlightBrand for the review. Check their store, I was genuinely impressed by the amount of flashlights they have: https://www.flashlightbrand.com
And here you can buy this flashlight: https://www.flashlightbrand.com/convoy-s21a-sst40-6500k5000k-kw-cslpm1tg-sft40-search-light-p4073429.html
Or other Convoy lights: https://www.flashlightbrand.com/Convoy-Flashlight-c134171/
Table of Contents:
- General parameters
- Package content
- Appearance, parameters
- UI, runtime and charging
- PWM
- Waterproofness
- Light pattern, tint
- Usage and my experiences
- Gallery and Summary
General Parameters
Material: Aluminium alloy
LED: Luminus SFT40 6500K
LVP: Yes
Reverse polarity protection: Yes
Lens type: AR coated glass lens
Reflector: SMO (smooth, more throw)
Mode memory: Yes
Tailstand: Yes
Battery: 1x 21700 flat top unprotected (not included)
Modes: 4 modes 0.1% - 3% - 30% - 100%/12 groups (Biscotti), max current 6000mA, internal temperature protection (I changed mine to group 10: (1%, 10%, 35%, 100%))
Size (length x width): 123mm x 26.6mm
Weight: 88g
Package content
As usual, Convoy flashlights don't come with a bunch of stuff, this time it was the flashlight + lanyard.
Everything secured by bubble wrap, in small white package.
Appearance, parameters
S21A looks definitely like older and beefier brother of S2+
To be honest, it looks exactly like the S2+. It is just bigger, with slightly better heat dissipation than S2+. Still not good heat dissipation, but better, only because it is heavier.
S21A is a little bigger than S2+, but keep in mind it fits 21700 cell, so it is not that big. It is small, in fact. Look at this comparison:
And yes, my S2+ is doing great, no worries.
But a quick word about S21A:
Starting from the front, we have an AR coated glass lens
and an SFT40 LED, with max output of 1460 lumens. If you want something between thrower and flooder...ok maybe not between, let me start again: If you like throwers, but also want something with a bit of light spill, the SFT40 is for you. It has long distance with a bit of spill, so you won't end up with a laser-flashlight.
Greased square cut threads with o-rings on both sides. As we discover later, this is enough for very good waterproofness.
Tailcap with a mechanical reverse switch, good and universal option. The spring is good, not the thickest of all time, but enough for a small flashlight.
Sadly, it is hard to get to the diode, because there is no unscrewable bezel, so I was unable to check for thermal grease condition and if screws are tightened securely (if there are any screws).
UI, runtime, heat dissipation and charging
UI
Biscotti-like UI with 12 groups, each with different modes set. Default group: (0.1%, 1%, 10%, 35%, 100%, strobe, bike flash, battery control). I don't find the last 3 modes that useful, so I switched to group 10, which is: (1%, 10%, 35%, 100%)
Runtime
Pretty normal runtime, nothing special. I tested a 35% mode, about 648lm. It lasted ...
Here is the runtime graph of 35% brightness, 648lm:
It seems like Convoy moved a step forward from a flat brightness - runtime curve to rising curve :P
Heat dissipation
Heat dissipation is...is there. But I didn't expect anything great from that design. Don't give me wrong, it can dissipate heat, just look at the graph and my temperature readings:
Temperature after given time on turbo:
At 2min: 56°C
At 5min: 56°C
At 10min: 60°C
Brightness at 10 min: 600lm
It looks fine, but luckily I was curious if the flashlight would get hotter after my standard 10 min test. Unfortunately, it got. Oh boy, it indeed got.
After 10min (so total 20min after turning on) it reached 66°C and brightness decreased to 592lm.
After next 10min (so 30min total) it reached, and stabilized, at 70°C and 586lm. It was VERY hot, definitely way hot to carry, even the tailcap was at 57°C
It seems like the driver doesn't have a constant temperature checking + brightness decreasing, but checks temperature constantly and decreases it only once each time you power the flashlight on and it detects overheating. Maybe I'm wrong, but why it behaves like this then?
It was definitely not as bad as my tests with Mateminco S03, which reached 100°C and I brewed a tea using the flashlight
To this day I wonder why they don't want to send me flashlights for reviews anymore...
Charging
You have to manually remove a battery from the flashlight and put it in Li-Ion charger. You can remove it by unscrewing the tailcap. It's a lot of work, I know, but if it's not your day you can ask someone for help.
PWM
Did not observe any flickering on the lowest mode. Good
Waterproofness
Convoy generally doesn't add an IP rating, but those flashlights are usually waterproof, and won't leak any water even when submerged. Is this the case here? Let's find out.
I submerged my S21A for 2 hours and it did not leak. Great.
Light pattern, tint
SFT40 LED, cool white, max output 1460lm (my measurements). SMO reflector in pair with a throwy LED gives...you guessed it, a good throw.
Light pattern is very nice, as mentioned, with a bit of spill. And also without a tint shift, definitely good.
Usage and my experiences
Convoy makes sturdy and durable flashlight. I think I will be actually using this one, instead of putting it on shelf...
Thermal regulation has been done not very carefully, as it triggers once. I don't know how the UI code looks like, but it seems that the thermal stepdown trigger is not looped. Or maybe I'm wrong.
I am now wondering if all Convoy flashlights have the same issue, and because S21A has poor thermal dissipation we can notice that here, and not in other flashlights.
In any case, it is not a deal breaker for me, as it is not dangerous - unless someone decides to glue the S21A to his hand and turn the turbo on... but in other cases it is not harmful.
Summary
Convoy S21A is a compact flashlight with minimalist design. Don't be fooled by its design, though. Equipped with 21700 cell, and thanks to SFT40 LED it can output up to 1460lm and work for many hours on lower modes like 35%. Waterproof rating (or lack of it) doesn't mean you can't use it in heavy rain. Convoy flashlights are generally waterproof, and this one is not an exception. Just remember to not glue it to your hand and turn max brightness...
Pros:
+ Max brightness 1460lm
+ Small size
+ No tint shift
+ Waterproof
Cons:
- Thermal regulation trigger is not looped, activates once every turn on
- Poor heat dissipation
Again, thank you FlashlightBrand for sending this flashlight.
FlashlightBrand official store: https://www.flashlightbrand.com
If you have any questions, put them below, thanks for sticking for a while :)