[Review] Klarus XT1A (2018) (1000 lm, Dual tail switch, XP-L HD, 1x14500/AA, on-cell charging)

bmengineer · 2018-10-24T17:39:02.000Z

The Product

Klarus XT1A (2018)

Today I’m taking a look at the Klarus XT1A (2018). This is a light that runs on a single AA or the included 14500 cell. The light uses a Cree XP-L HD emitter, and has two separate switches on the tail. The included 14500 has built in micro-USB charging. This light claims a maximum output of 1000 lumens, which is quite high compared to other AA or 14500 options. Note that there's an older, and much different, version of the XT1A that Klarus makes as well.

This light was kindly provided by GearBest, and is available from them by following this affiliate link.

Spoiler

I was excited to try out this light thanks to two features that make it stand out from the competition - the huge output for the form factor, and the dual tail switch.

The dual tail switch is great. In the outdoor mode, it gives quick access to momentary high, momentary low, constant high, and constant low. In a pocket sized light, momentary access to two commonly used modes is great for pulling it out and taking a quick peek at something, whether it’s finding some socks in the morning, looking for the keys you dropped, plugging in a cable under a desk.

The output on the light is definitely high, but the light is much larger than most AA offerings, and even larger than some 18650 lights. This probably necessary to make the dual tail switch work, but it makes the high power less impressive. I also noticed some flickering on the highest mode.

I’ll also note that being able to quickly charge the cell with a micro-USB cable, which I’m likely to have with me everywhere I would need to top it off, is very convenient.

Size

This light is certainly large. It’s both wider and longer than other AA lights I have, and even larger than some 18650 lights - although those don’t offer the dual tail switch setup this light does. I measured it at 108.5 mm long, and 23.4 mm at the widest point (the hexagonal portion just behind the head).

Sofirn SF14 (AA), Skilhunt H03 RC (18650), Klarus XT1A (AA), Convoy S2+ (18650)

Build

This light is large, but it feels extremely solid as a result. The bezel, like the rest of the light, is made from black anodized aluminum. It’s smooth without crenelations, and has a ‘hot’ warning etched into the coating. The opposite side of the light has some regulatory markings, which aren’t shown in the image. Looking just further down the light, you can see the larger hexagonal portion behind the head that works as a great anti-roll feature. The small circle on that section is a status LED that will turn green, yellow, or red when the light is switched on to indicate cell voltage.

The head of the light

The body of the light is devoid of any traditional knurling, but there are some grooves cut in for grip. One side has the model name and serial number etched into the coating, and the opposite side has the brand name. Towards the tail, there’s a single groove for the tail clip.

Body and pocket clip

The tail is where this light’s most interesting feature can be found. There’s a traditional forward clicky switch, but also a paddle switch. The paddle is a steel plate hinged on the two ‘wings’ of the tailcap, which depresses a rubber e-switch beneath it. This tailcap design does mean the light does not tailstand, since the switches are proud of the rest of the tail.

Tailcap

In order to enable the dual tail switches, the tailcap and body of the light can not be disassembled. The cell is inserted by removing the head of the light. The threads are not anodized, but the light can still be locked out with a slight turn. There is a brass button on the PCB for the positive contact.

Head threads and positive contact

The tube is dual walled so the signal from the switch can be passed forward to the driver. The tail end of the light uses a spring for the negative contact.

Dual tubes and tail spring

What’s Included

The light ships in a black and red cardboard box. All the accessories and the light are in the box, and the light is held in a plastic cradle.

The included kit

Klarus XT1A (2018)
14500 cell with micro-USB charging
Pocket clip
Micro-USB charging cable
Lanyard
Spare o-ring
Paperwork

Ergonomics and Retention

The added size of the light means it fits well in the hand, and tail switches are known for being easy to access with one hand - no complaints about ergonomics with this light. The two tailcap buttons are different in shape, size, texture, and elevation, so it’s easy to tell them apart by feel.

There’s a single hole in the tailcap to attach the included lanyard. The clip can only be attached for head-down carry, and is not particularly deep, but iit does the job well. The shape is good, and I had no issues clipping it on to my pocket.

Modes and Interface

This light actually has two independent user groups - outdoor and tactical. The light came with the outdoor mode preset, and it’s the one I prefer to use. In the outdoor group, there are 3 modes - low, mid, and high. The UI is as follows:

The clicky switch turns the light on in high, and can be depressed slightly for momentary high. Repeat this press to turn off.
The paddle switch serves as momentary low, or will turn the light on in low if held for a few seconds. Repeat this long press to turn off.
Once on in low or high, the paddle switch cycles through the brightness levels.
There’s also an SOS flash that can be accessed by long pressing the paddle switch after turning the light on with the clicky switch - I like that this mode is hidden.

There’s also the ‘tactical’ UI. This caters to a lot of people looking for a tactical light, but isn’t what I personally want out of an EDC light. In this UI:

Clicky switch starts in turbo. Paddle cycles modes once on.
Paddle is momentary strobe. Holding down for a few seconds will leave the light on in strobe. Once on, paddle switch cycles between high and strobe.

This is great for having the most disorienting modes at a single press, if that’s what you need.

One thing that needs to be discussed is the mode spacing - with the included cell, the modes claim to be 5, 80, and 1000 lumens. That’s a huge jump from medium to high. In practice, I really don’t mind this. It really encourages me to use the lower modes, and I find the quick access to both low and high extremely convenient. That being said, I would probably prefer a second ‘mid’ mode be added in there somewhere. With an AA cell, the modes change to 5, 80, and 300, which I much prefer.

Light Quality and Beam

The emitter chosen in this light is a, XP-L HD, set in a smooth reflector. There are emitters I like better than the XP-L, but I think it’s a good choice for this kind of light. It has cool white tint, but the beam is quite functional.

One thing to note is I saw some very noticeable PWM on high mode only with both the included 14500 cell and my own NiMH cells. I’ve never seen a light that flickered only on the highest mode, so I don’t really know what the cause is. Since I mainly used the lower modes and only used high for “what’s hiding in that bushes” sort of quick peeks, it wasn’t a total deal breaker - but it is noticeable on my sample for sure.The lower modes were smooth, with no visible flicker or PWM.

Power and Runtime

With the included cell, the light ran on high well over the hour claimed on the label. There’s a large step down about 10 minutes in, but that can only be expected in a light this size managing the heat from a 1000 lumen output. After that the run was steady at about 40% until it stepped down to a very dim moonlight. In this mode it could be reset to a brighter level, but would quickly drop back down. The test was stopped manually as the indicator LED was blinking rapidly to indicate low voltage.

Runtime on high with included 14500

Tests were also run with NiMH cells. Note that the Ikea Ladda cells I used are particularly low capacity, and you can expect much longer runs from higher capacity cells. The runtime on high bounced around a bit, it looks like the driver had some trouble pulling the power it needed from the cell used. On medium, the output is perfectly steady for over an hours before stepping down to low, finally dying after about 2.5 hours. This is really great performance, given the lower capacity of the cells used.

Runtime with NiMH AA cell

Charging

The included cell has a handy micro-USB port built in to the cell itself. Charging from a dead cell took just over 3 hours to complete, and ran at just over 0.3A. This is a low charge current, but it’s safe for this smaller cell, and will help maintain the cell capacity. I would say this is a good charge curve. Note that the voltage displayed on the graph below is measured at the USB input, not at the cell terminals, and is basically meaningless.

Charge curve

Summary

Pros:

Great shortcuts to momentary high, momentary low, constant high, constant low in outdoor UI
Configurable UI lets you use tactical mode if you prefer that
High output for an AA sized cell
Full kit - comes with a cell with built in charging
Runs on either a high powered 14500 or an easy to find AA cell

Cons:

Flicker on high mode
Mode spacing has a big jump between medium and high
Light is very large compared to other offerings with this cell size

MascaratumB · 2018-10-24T23:35:29.000Z

Hey mate, thanks for your review
I bought this light but due to customs issues I didn’t get it and now I’m thinking to go for the XT1C, that is almost the same, but for the 16340s!

But please, tell me, does the XT1A only uses the button top batteries, or a flat top (let’s say a Sanyo 14500 or a Efest IMR) would also fit? Just asking ’cause the Wuben E05 only takes “long” button top batteries (a Sofirn 14500 doesn’t fit for being small…)

Again, thank you

bmengineer · 2018-10-25T01:24:25.000Z

Thanks for reading! It definitely doesn’t need long batteries since it works fine with NiMH, I’ll check my efests in it tomorrow. Any other questions?

bmengineer · 2018-10-25T17:43:57.000Z

I took a peek for you, my Efest 14500 cells have no issues with fit, light works just fine with those.

MascaratumB · 2018-10-25T18:04:14.000Z

bmengineer:

I took a peek for you, my Efest 14500 cells have no issues with fit, light works just fine with those.

Hey mate, thanks for checking it out To have some versatility is quite good, an having only unprotected cells and 2 short button tops, I wanted to be sure!

I am still on the line to get this or not (and take the XT1C), but at least I know it takes those cells!
Thanks for taking the time to check :+1:

bkp · 2018-10-31T17:21:01.000Z

Great review.
I just received my XT1A yesterday and too am experiencing the ‘flickering’ you referenced. However, mine does it in a particular way. With a 14500, it might flicker for about 10 seconds (maybe 20) then it seems to normalize. With an AA NiMH (Eneloop Pro) or Alkaline, it always flickers. Here’s the weird part, it only does this when activated from the primary switch (round, forward clicky).

When using the ‘mode switch’ and cycling from low -> med -> high, I never see the flicker regardless of battery type.

I didn’t notice any comment from @Narmattaru of this in his review, so I’m wondering if there’s a faulty batch. I have an email out to Klarus, I’ll post if given any direction.

bmengineer · 2018-11-01T10:31:01.000Z

bkp:

Great review.
I just received my XT1A yesterday and too am experiencing the ‘flickering’ you referenced. However, mine does it in a particular way. With a 14500, it might flicker for about 10 seconds (maybe 20) then it seems to normalize. With an AA NiMH (Eneloop Pro) or Alkaline, it always flickers. Here’s the weird part, it only does this when activated from the primary switch (round, forward clicky).

When using the ‘mode switch’ and cycling from low -> med -> high, I never see the flicker regardless of battery type.

I didn’t notice any comment from @Narmattaru of this in his review, so I’m wondering if there’s a faulty batch. I have an email out to Klarus, I’ll post if given any direction.

That’s strange. Maybe something about the way the two tubes are arranged is causing it?

Thanks for reading, and sorry you’re having trouble.

junglejim13660 · 2018-11-10T01:39:35.000Z

I just got my XT1A today. My light has the exact same problem with flickering. Cleaned the contacts inside the head and on the barrel, I even tried 3 different brands of 14500 batteries, none of these solutions have worked. I’ll contact Klarus on Monday.

bmengineer · 2018-11-12T01:46:31.000Z

That’s disappointing, let me know how it works out

HONDARIDER · 2018-11-12T03:45:02.000Z

Mine seems to not have any flickering issue. I do wish it had a 4 or 500 lumen mode instead of the junp from 80 to 1000. Even a 200 lumen mode would work better.

bmengineer · 2018-11-12T13:27:04.000Z

If you’d prefer a lower high, you can always run it on a NiMH cell - That’s what I’m more likely to do.

bkp · 2018-11-12T14:43:46.000Z

I’m still awaiting further direction from Klarus, I’m not sure if they’re going to replace it or have me send it back for repair.

Another thing I noticed, the XT1A (at least mine) doesn’t work with a lithium primary (L91).

junglejim13660 · 2018-11-12T17:57:26.000Z

I over tightened the head to the barrel and the flickering has stopped. Shouldn’t have to do this with a new light. I found the Nitecore NL1485- 850mAh 14500 will not work in the XT1A due to it’s additional length. If this continues to be an issue, be sure to make a video showcasing the flickering, Banggood wants video proof of your issue.

bkp · 2018-11-12T18:02:15.000Z

Flickering with the provided Klarus 14500 is intermittent on mine. seems worse when freshly charged. the flickering is persistent with a NiMH or Alkaline, and over-tightening didn’t seem to make any difference.

Bravi · 2018-11-27T06:05:31.000Z

I FIXED THE FLICKER!

I just received this light a few days ago and noticed the flickering only on HIGH output. It also wouldn't let me change the output levels while it was flickering.

Based on junglejim13660's comments, I looked at the electrical contacts. Initially, I thought the contacts were the body threads themselves like a Surefire—but then I noticed the gold-ish ring inside the head unit (top of picture), and the very thin inner ring on the tail body (bottom of picture). It made sense to me that it was trying to push higher amperage across what is essentially a one-man rope bridge causing the flickering.

I grabbed a very flat knife sharpening stone and very carefully 'lapped' the tail body contact ring (bottom of picture)—almost as you would lap an AR-10/15 upper receiver—so that it would have a more even and flush fit with the head unit contacts. I cleaned the contacts and reassembled the light. No more flicker!

To check my theory, I loosened the body a tiny bit; just enough so that the connections made contact. Behold, the light flickered again. I tightened it back up with normal torque and the flicker is gone once again. The one-man bridge has been upgraded to wood. I assume the lack of bare aluminum contact surface is a compromise for a thinner overall body. Though, this fix is something that can be easily done in the QA process.

junglejim13660 · 2018-11-27T20:22:36.000Z

Good fix Bravi. I’m going use your method to permanently stop the flickering. I was also thinking that one or both of the mating surfaces were machined out of round.

I hope everyone who has this issue finds your post!

MascaratumB · 2019-02-04T15:03:00.000Z

@ bmengineer or anyone that has this light: is the bezel removable (even it if is “hard” glued)?

bmengineer · 2019-02-04T18:29:06.000Z

I couldn’t get mine off while I still had it, but I didn’t try any tools or heat.

MascaratumB · 2019-02-04T22:01:19.000Z

bmengineer:

I couldn’t get mine off while I still had it, but I didn’t try any tools or heat.

Thanks for the answer! I believe it is probably glued the hard way! I’m just making eventual plans for when my XT1C arrives :smiling_imp:
Thanks again! :+1:

bmengineer · 2019-02-04T22:52:17.000Z

MascaratumB:

bmengineer:

I couldn’t get mine off while I still had it, but I didn’t try any tools or heat.

Thanks for the answer! I believe it is probably glued the hard way! I’m just making eventual plans for when my XT1C arrives :smiling_imp:
Thanks again! :+1:

Just for curiosity’s sake, let me know if you manage to get into it.