Weltool M8 review

"An efficient, durable tactical zoomie with a spec under 50,000lm? U WOT M8?"

"So for my second full review, I'm doing another twisty light? Well, kind of..."

The Weltool M8 is a rugged tactical zoomie using a round die LED and a twisty zoom mechanism.

Updates

• 2023/12/02: Added detailed spectrometer readings

Introduction, Background, and Official Specs

The Weltool M8 is a single-LED zoomie with a rotary zoom mechanism. "Zoomies" often have a lot of appeal to non-enthusiasts, and many an enthusiast's old light before they went down the rabbit hole was a cheap (or just overpriced...) AA-powered zoomie, often with next mode memory, strobes in the main rotation, and/or a claimed output higher than the Imalent SR32. I myself first joined the enthusiast community when I was looking for a replacement for a failed such light myself, and close to a year later, I'm reviewing lights...

It's understandable why zoomies are easy to market - flood/throw is a useful concept, yet there's a reason that so many flood/throw enthusiast lights exist with other mechanisms such as separate LED sets, or even electro-optical technology, that avoid the disadvantages of a physical control mechanism, but it is an understandably satisftying feeling to be adjusting it mechanically, even if overall the disadvantages of a physical mechanism (weight, poor waterproofing, inefficiency both optically and thermally, and relative lack of durability) make it a rare choice, but there is definitely demand, as shown by the Convoy Z1 and by the recent meme-level popularity in 2023 of the Acebeam Terminator M1.

The Weltool M8 is an LED zoomie designed, like most Weltool lights, with ruggedness in mind. It also a Yinding round-die domeless LED (the exact LED is not specified, and spec sheets or even an exhaustive list of models are not published by Yinding). These LEDs are still relatively rare, but offer a high intensity and a smooth circular beam without artifacts. This fixes one common problem with zoomies, that when the beam is "zoomed" to throw mode, the hotspot is normally square to match the emitting surface of the LED. Many cheap zoomies also use a mechanism where the head slides in and out to adjust the focus; this mechanism has a relatively low durability and in particular, bad waterproofing as the volume of the head changes, causing water to be sucked in if the zoom is changed in a wet environment. The M8's rotary zoomie mechanism should offer better sealing as well as being more durable. Weltool do not publish an IP rating; when I emailed to ask I was told IP55 - this is rated as dust and water resistant, but not for submersion. I did not test the IP rating, but this should be sufficient for use in heavy rain or a brief dip into water (although I personally would avoid operating the zoom mechanism excessively when wet, just to make sure). This is not perfect, but still significantly better than the majority of zoomies.

The M8 is powered by one 18650 or 2xCR123A batteries. My light came with a Weltool-branded button-top 18650, which the label says is 3000mAh. I used this battery for all tests - I did not test performance with CR123A due to not having any available.

Official specs:

I purchased this light with my own money via a reseller. I am not being compensated for this review and do not have any kind of referral or affiliate agreement with any sellers.

First Impressions

The light comes in a cardboard box typical of most Weltool packaging I have seen, which contains a slightly fancier box. Inside, there is the light, a USB battery charger, USB-A to USB-C cable, instruction manual, a certificate of quality, and a spare o-ring, as well as the light, with the battery inside. The pocket clip was preinstalled on the light.

Physical Design and Build Quality

The M8 shares physical design cues with other Weltool lights, in particular the long tailcap with large protruding forward clicky tailswitch. and the long flared head with the lens set slightly further back from the end than many lights. The aspheric lens is protected with a flat glass lens in front of it, set relatively far back from the bezel (another common design element in many Weltool lights), which should help prevent scratches when carried in a pocket or bag.

The light is finished with black anodisation. Weltool does not specify the type, but it feels very hard and has an extremely pleasant, smooth feel. On one side of the head, there is the Weltool logo, the model and name (another common Weltool design element - many of their lights have cool names like "Iron Fan", "Dragon in Clouds, "Thunderbolt", and... ah... "Vegetable Gardener"?). On the other side, there are regulatory marks, the usual "hot" symbol, as well as a line of dots indicating the rotation direction to adjust the zoom.

The body tube is covered in diamond pattern knurling that provides excellent grip, although the end of the pocket clip does sit on the knurling so this light has some "pocket shredder" potential - certainly, I have not tried carrying it clipped much. The clip is extrenmely stiff, I need to use a thumb to lift it to clip it to something, but the light does feel extremely secure when clipped. Note that this is not a deep-carry clip; when clipped to a pocket the head will protrude a fair amount. Since overall, this light is clearly intended as a tactical light, I don't see this as a huge problem, as it is easy to grab from its clipped location quickly. Overall, I am not a big fan of clips that snap into a groove on the body as many tend to rotate and cause unnecessary scratches, and some detach from the light body easily if pulled onip is one of the best of its type and it stays put without rotating, and I did not at any point when test carrying it feel like it was at risk of separating.

The forward-clicky tailswitch is big and protrudes fairly far past the end of the tailcap. It has a domed shape so the light can not tailstand, and is easy to operate in a hurry or when wearing thick gloves, again fitting the overall Weltool design language. I like this overall design concept; this is a light that is easy to handle in many different situations, although I did find myself wishing it had some kind of raised retention ring towards the tailcap or a larger flare on the tailcap similar to the W3 Pro Tac, a light that I often carry any time I feel that I might need a defensive light. With the M8, the tailcap slips through the fingers a little more easily.

The zoom mechanism works by rotating the head - there is a raised ring on the head with grippy cutouts to help with this, but the tailcap is not particularly tight, so it is possible to accidentally switch the light off by untwisting the tailcap. Since the switch is a forward clicky, this is not a huge problem as the tailcap can just be retightened, but this does cause it to return to high mode if it was on medium or low. The head twists 180 degrees to adjust the zoom, where fully clockwise (with the light facing away from you) is 100% flood mode, and anticlockwise for throw mode. The action of the zoom mechanism is very smooth and takes relatively little effort to operate; it is possible to hold the light and adjust the zoom one-handed - I found this easiest holding the light with a reverse grip, with which the ridges on the head fall nicely under my thumb.

The light is relatively long for an 18650 light, being longer even than a fair number of 21700 lights that I own and arguably not that far off the length of a medium sized LEP, but this is largely unavoidable with the zoom mechanism, and it is very slim for its length, leading to it still being overall easy to carry, although the lack of a deep carry clip means the head will always be exposed if carried clipped. I found it carryable in most jeans pockets and all but the very smallest purses, but if you're trying to Tetris everything to the maximum, you may find it a little inconvenient - it's definitely not a light you can forget you're carrying due to its length.

Size Comparison

I took comparison photos of the M8 with a mixed selection of EDC, tactical, and flood/throw lights.

Group 1, left to right:

• Wurkkos TS25
• Emisar D4K
• Acebeam Terminator M1
• Wurkkos TD04
• Weltool M8
• Weltool W3 Pro Tac with short tube

Group 2, from left to right:

• Loop SK01S LEP
• Noctigon DM1.12
• Weltool M8
• Fenix PD36R Pro
• Weltool W3 Pro tac
• Acebeam L19v2

User Interface

There is no lockout mode, but the light can be mechanically locked out by untwisting the tailcap slightly. In addition, I found the mechanical switch reasonable for pocket or purse carry without it accidentally coming on, although I would mechanically lock it out before putting it into a backpack or similar. Low mode is relatively difficult to enter, and requires both good timing and some practice. There are no strobe or other blinky modes, and no battery check mode, although the light will blink when battery is getting low. The driver has LVP; in my testing then I was able to discharge the battery to 3.0V before the light was putting out <1lm so LVP has a relatively low threshold.

The driver has a low voltage warning - for a minute or so before the light drops to a very low (~25lm) output, it starts blinking for several seconds. There is no battery check mode or any other way battery level is indicated.

Driver and Emitters

Weltool do not specify the driver type, but the Yinding round die LEDs are all 3V, and the 2xCR123A compatibility leads me to think this is most likely a buck driver, as my performance testing shows excellent regulation after a relatively rapid initial stepdown. This is an inherent disadvantage of zoomies - the mechanism is thermally inefficient and heat stays in the LED rather than be conducted to the body. Weltool opted to solve this problem by using an efficient driver with very effective regulation and driving the emitter at a fairly low power, as well as some reasonably active thermal management; in my testing, the M8 never got more than slightly warm to the touch.

The LED offers a high intensity and a smooth circular beam without artifacts. When zoomed to throw mode, there are a few small beam artifacts visible in a square shape, likely caused by the actual chip package of the LED, but the hotspot overall is circular, and they artifacts will be dififcult to notice for the average user as most owners of this light are unlikely to be white wall hunting with it. Note that this is not a light for people who are fans of a clean beam, as when fully zoomed, the tint of the hotspot is uneven, with spots of phosphor visible at close range, although these disappear if zoomed to any value below maximum throw, as well as outdoors. In my opinion, for the intended uses of this light, this is not partcularly a problem, and if you zoom it even a little towards flood, the beam smooths out to an average low-CRI cool white. Given the magnifying effect of the aspheric lens, this effect is also to be expected with any LED, and will be present on any zoomie - a reason many high-end zoomies are LEPs and not LEDs. In flood mode, the beam is very wide, perfectly circular, with smooth spill, and a small relatively dim corona at some focus settings. Overall, I would say that the beam resembles that of an LEP more than any other LED light.

I measured the LED's CCT and CRI with an Opple Light Master 3 and 4. Note the LM4's R9 value is well known to be incorrect; I seriously doubt this light has 100 R9 ;)

Opple measurements:

Updated 02/12/2023: I now have a better spectrometer, here are some more accurate measurements:

Power and Charging

The M8 comes with a button-top 3000mAh 18650 battery, as well as a USB-C single-cell charger. There is no built-in charging on either the battery or the light itself. There are dual springs, and the light is also able to use normal flat-top batteries, as well as 2xCR123A. I did not test with any CR123A as I do not have any available, but I would expect a lower output on high and lower runtimes with them - the main use case for CR123A would be for extreme cold, or a light stored either in extreme conditions (e.g. inside a vehicle) or for a long time.

Moddability

Likely very low. The head and body tube are a single piece with no obvious method of disassembly.

Do you have teardown photos? Email me or DM on BLF or Reddit if you are interested in me using them (with credit given).

Performance

As previously mentioned, most zoomies have terrible thermal performance. To compensate, Weltool have used a very throwy LED driven at a relatively low power, and the thermal stepdown is both immediate and relatively aggressive. Weltool give a spec of 810lm for the high mode; my light was not able to reach that, so I am not sure if this is OTF lumens, or output at the actual emitter, as most zoom mechanisms are inefficient and often result in the loss of a large portion of the LED's output. I own several other Weltool lights and this is the only one I own that comes in significantly under spec - note that a 10-15% margin of error is reasonable with my current equipment, but the highest value I was able to get was 651lm, or 76% of spec.

Most zoomies are significantly brighter in either flood or throw mode, as due to the nature of how how the zoom mechanism works, the optic can only be most efficient at a single position. Visually, I did not notice a lot of difference between flood and throw modes, although my lumen tube registered a higher reading in flood mode. I experimented a bit with adjusting the zoom with it in the tube, and found that the highest reading I could get (651lm) was with it adjusted most of the way towards flood, but not on 100% flood. The exact position most likely varies based on environmental factors, but if I had to guess, I would call this approximately 80% of the way towards flood. Either way, I could not notice any significant visible difference between it and 100% flood, while flood mode read somewhat brighter than throw in my lumen tube.

All lumen measurements taken using a 4.5 inch Texas Ace lumen tube. Candela measurements were performed indoors at a distance of 4m, using a UNI-T UT383BT.

Runtime tests were performed using the lumen tube's HS1010A luxmeter, which the tube is calibrated for, with data recorded via taking a video, exporting the individual frames using ffmpeg, and parsing the value on the luxmeter's display at the appropriate frame for each measurement. This method is essentually automated manual work, so I reduced the data interval over time. I logged the value every second for the first 5 minutes, every 10 seconds for the first 1 hour, then every 30 seconds afterwards. Each test was stopped when the lumen tube registered <1 lm as this is its current maximum precision.

Output and Throw

High

Medium

Low

Runtime

The M8 comes much closer to its runtime specs than lumen specs. If I consider the end of the runtime to be when the light does a sharp drop to ~20lm, these are the results:

High

Medium

Overall, the M8 comes close enough to specified runtime that my results are within an acceptable margin of error. I only tested flood on medium and did not test low runtime; I only have so much time. I would expect it to meet or slightly exceed spec on low given the above results.

Beamshots

Competitors

The Convoy Z1 is available significantly cheaper and offers some higher performance LEDs such as CULPM1 (W2.1) and SFT40, but does not have the same durability or build quality as the M8. Sustained performance is likely worse than the M8, and Convoy's UI may be considered an avantage or a disadvantage depending on your perspective - personally, I significantly prefer the M78's UI despite it lacking a battery check and strobe mode, but in general IU consider the UI the worst point of Convoy's reverse clicky lights.

The Jaxman Z1 is another zoomie similar in physical design to the Convoy Z1, with somewhat higher performance icluding series battery options for 6V LEDs, and costing around twice as much at ~$60.

A review of a twisty zoomie wouldn't be complete without a mention of the Acebeam Terminator M1. This is a hybrid LEP/LED light, with the zoom mechanism on the LEP. Compared to the M8, it throws further with the LEP but has a less wide flood mode, and while neither are going to win any praise specifically for the tint, the M1's beam is possibly slightly more consistent, and the 21700 battery and added convenience of USB-C are bonuses with the M1 along with the separate flood LED channel providing a more traditional flood beam profile with a triple TIR, but on the other hand, the M1 is significantly more expensive, and much less rugged - in particular, the omission of a glass lens to cover the LEP's aspheric is a big negative point. Acebeam are also known for efficient drivers with good regulation. that are generally similar to Weltool's in efficiency.

The Noctigon DM1.12 is a more enthusiast option, and lacks a physical zoom mechanism in favour of separate LED sets and optics. While Hanklights generally have reasonable durability, it is not their specific design goal, although the lack of moving parts does somewhat offset this in both durability and weight. The DM1.12 has significantly higher output (especially in flood mode) and general performance as well as a broad selection of LED options and optional 26800 tube, and is available at a similar price point. The main point of comparison for the DM1.12 is that it has electronic infinitely variable flood/throw, so avoids the disadvantages of a physical mechanism, but this light is also aimed at a different market, primarily targeting enthusiasts rather than general tactical/EDC usage, and while it is shorter with a larger battery capacity, it has a very flared head that makes it less easy to carry in a small pocket.

The Acebeam W35 LC DEL is another LEP zoomie, this time with an electro-optical zoom mechanism. This is a significantly higher priced option (above the Terminator M1) but has excellent throw performance and similar flood, but the electronic flood/throw adjustment is stepped rather than infinitely variable.

Final Thoughts and Score

Overall, I really like the Weltool M8. While it comes in under spec in most tests, it still comes reasonably close, and making a zoomie with good general characteristics is definitely a difficult engineering challenge, and I am happy with this light overall. I particularly like the round hotspot when zoomed to throw mode, compared to many zoomies that have a square beam. Let's be honest, zoomies are fun. Most enthusiasts are familiar with the drawbacks know how bad most are, and this is possibly the least-bad option for a light that you might want to actually carry, especially as an only light. In fact, my partner likes it so much that a second one is on its way to me right now for a Christmas present, so it finally displaced her "ultrabright" "tactical" AA zoomie. If someone is really set on a physical zoom mechanism but you want to find them something decent, this is certainly a great choice.

The Weltool M8 can be purchased directly from Weltool here, or from various resellers.

Thanks for everyone's support - these reviews take me a lot of time to do, and I'm still working on my reviewing style and would appreciate any feedback. I am active on BLF or Reddit, both on /r/flashlight and other specific subreddits, and have started my own subreddit for review content at /r/WolfgirlReviews. In particular, I would be interested in people's thoughts about size comparisons - am I providing enough common points of reference, or is there a specific popular light I should include to provide one?