Wurkkos HD01 Review - flat EDC with laser, floodlight, and RGB

"The Wurkkos HD01, with precision aimable strobe mode!"

"Arkfeld killer? Maybe."

The Wurkkos HD01 is a small EDC light with a built in battery, white/RGB side LED, and a class 3R green laser.

Updates

May 2024: Confirmed that the laser artifact issue has been fixed for the second and subsequent production batches, as well as the battery rattle issue.

Introduction, Background, and Official Specs

Wurkkos hinted the HD01 earlier in 2024, and released it in April. The HD01 is aimed at the "small EDC" market category, and incorporates what appear to be the same side LEDs as the Sofirn IF24, but in a much smaller form factor and with the addition of a 5mW green laser. The small flat light form factor has seen interest recently due to the Olight Arkfeld, with TrustFire and Nitecore also releasing flat lights recently. These lights often have multiple different emitters in one light, and Wurkkos have opted for a green laser, and an option so far unique in small flat lights, a white+RGB flood LED strip (shared with the IF24).

Official specs and test results:

General information:

For runtime testing, I give two figures when possible. The ANSI FL1 runtime is calculated by when the light drops below 10% of initial output. I also attempt to run the light past this to find the point where it switches off automatically if possible. Many lights will run at 1 lumen of less for an extended time before powering off, and with these lights I note my observations on when the runtime test was terminated, and may terminate tests at this point as my current measuring setup has a minimum of 1 lumen. For testing of output, my acceptable margin of error is between 5% and 15%, with margin increasing with output.

I was sent this light for free by Wurkkos in exchange for a review. I am not receiving any commission for sales, and am giving my honest opinion without holding back on any negative experiences or overstating any positive. I may use affiliate links to Amazon or similar sites for things such as measuring equipment I use, but do not otherwise have any related interest in anything I mention.

First Impressions, Physical Design, and Build Quality

The HD01 is a unibody design, with no obvious method of opening, as it uses a built-in lithium polymer battery. On the top edge is the Wurkkos logo and both switches, with a LED ring around each switch. and "HOT" and a serial number at the front by the emitters. On the left side when held facing away from the user is the side LED diffuser. Compared to the Sofirn IF24 which uses the same flood and RGB LEDs, the diffuser is narrower and more heavily frosted, rather than translucent, and the overall strip is about 20% longer than the Sofirn IF24's. "HD01" is printed on the side towards the front. The tailcap has the usual regulatory markings, and the opposite side is plain except for a USB-C charging port behind a rubber cover. On the bottom side, there is a pocket clip, attached using three hex screws, and underneath this, the surface is entirely rounded, so it relies on the clip to sit flat on a desk or table, although stability is good when doing this as the clip is wide, and the clip also incorporates a lanyard hole, although there was no lanyard in the box so if you want one, you will have to find your own. This is a reversible clip, although as it only runs halfway down the body of the HD01, it is possibly intended more for use as a hat light than for head-up carry, and people who use the clip will almost certainly want to carry head-down or half of the light will stick up from a pocket. The front of the HD01 is dedicated to the emitters, with a polycarbonate exposed TIR optic taking up most of the front face, other than a hole where the laser is located. The laser appears to be a separate optic placed within the TIR, and while in the course of testing and carrying the HD01, the TIR optic did pick up a few scratches, but the separate part over the laser did not, so hopefully this is glass rather than polycarbonate. While the exposed TIR is disappointing, it is of less concern with the main emitter which tends towards floody rather than having a lot of throw. I will go into more detail on this in Driver and Emitters.

The top surface of the HD01 is rounded towards the edges with a flat indented section in the middle that runs almost the entire the length of the light, including the switch area, which makes the HD01 easier to hold than if the entire top had been rounded, as it tends to catch your thumb and guide it towards the switches, with a gentle slope upwards to meet the rounded profile at each end. The USB port uses the typical rubber flap, and I would call the fitment average - while it never gave me worries that it would come open while being carried, and can be opened without feeling like it is at risk of breaking or being damaged, it also does not inspire confidence in its water resistance, with a relatively loose fitment, which is reflected in Wurkkos only giving the HD01 an IP65 rating, meaning it is rated as splashproof but not for immersion, overall a disappointing score for a light without a replaceable battery. The tailcap contains a medium-strength magnet, and the HD01 is able to support itself well on thick metal surfaces even when holding multiple sheets of paper, although on thin metal surfaces then its holding power is more limited and it can fall easily if bumped. The front of the HD01 is angled rather than straight - it is still able to headstand, but if you just casually place it down on its head without paying attention, it is likely to fall over, and it ends up standing at a slightly odd angle.

I did notice one quality issue with my HD01 - when shaken, the battery rattles inside it. I notified Terry from Wurkkos of this and he has stated that this issue was fixed for the second and subsequent production batches - at the time of writing, the first batch has entirely sold out so any new purchases are likely to be the revised version. Other than this, my HD01 was flawless, with a consistent smooth finish in the anodisation with no discolouration or inconsistent patches. The finish overall is matte, and held up well to normal carry and testing with no obvious marks or other damage.

Wurkkos's warranty is described on their website and is covered via the seller for the first 30 days, then after that, Wurkkos will repair the light within the warranty period (which seems to vary with different lights) if shipped to them.

Size Comparison

The HD01 covers several different categories of lights, so I used a combination of general EDC lights, work lights/mules, and RGB lights.

• Sofirn IF24
• Olight Arkfeld Pro
• Emisar D3AA
• Skilhunt Mix-7
• Fireflylite NOV-Mu v2
• Emisar D4K
• Emisar D4v2 Mule
• Wurkkos TS10
• Wuben X2

User Interface

Actions are given in Anduril-style notation. 1C means click once, 1H means click once and hold the switch. 2C means click twice in a row quickly, while 2H means click twice quickly, holding the second click.

As the HD01 has two switches, the forward switch controls the laser and side LEDs, while the rearward switch controls the main LED.

* Laser is always on when in strobe mode

** When using the forward switch to unlock, it unlocks to the laser being on, and the main LED if using the rearward switch.

I appreciate the ability to use the main LED and the laser at the same time, but this does end up with an odd combination in that the laser can be used in conjunction with the main emitter but not the side flood/RGB. However, the laser is still easy to control and quickly toggle off, so I still prefer this over the Olight Arkfeld Pro's much clumsier and slower implementation for the LED and laser at the same time, or the Sofirn IF24 where the main emitter can not be on at the same time as any others. Other than that one limitation, the laser can be combined and controlled separately without affecting the main emitter. Interestingly, there is one way to have all three emitters active, to activate the side LED first and then activate strobe, which activates the laser without switching the side LEDs off, although there is no way to change this to a useful state for all three, so this is possibly a UI bug.

The HD01's RGB modes are the same as the Sofirn IF24's, likely due to shared elements in the driver design, but the HD01's implementation here is worse than the IF24's - when ramping the RGB mix, the IF24's ramp is reversible by releasing and pressing the button, while the HD01's ramp direction is fixed, so if you miss the target you were aiming for, you have to go round again. In addition, several of the IF24's RGB modes are missing on the HD01. As with the IF24, there is no mode memory, and the police flash mode is first, which may be disruptive and annoying if trying to access one of the calmer modes such as RGB Waterfall.

As mentioned above, there seems to be no way to access strobe mode without the laser. I am not sure why a strobe mode might need precise aiming ;) - this is a nice feature to have optionally, but I question the logic of always having the laser active - while actual use cases for strobe are relatively rare and often involve some kind of self-defence context (as I doubt the HD01 is going to be a light of choice for many light painters), the use of the laser here is a complicating factor - while. In general, I would have preferred it if the laser was only able to be activated from the forward switch, as the use of the laser could be seen as a more hostile/escalating action compared to just a strobe, although at 5mW rated power, this is an eye-safe laser, so not dangerous. That said, I am not sure exactly of the use case for a laser simultaneously with the strobe mode - strobe rarely needs to be precisely aimed to have the intended effect.

There is no battery check mode - when the HD01 is first switched on, the switch LEDs light up in either green or red to indicate a normal or low battery, but there is no way to tell exactly how much battery you have left. The other use for the switch LEDs is toggled with 5C to enable a "breathing" effect where the switch LEDs fade from off to full power, then back to off. This mode will always use the green LEDs even if the battery is low - it might have been a nice extra touch to use the red instead on a low battery as a visual reminder.

Overall, this is a reasonable user interface. I'm not a big fan of many dual-switch interfaces overall, preferring a more advanced single switch interface for controlling multiple channels, but this is one of the better ones, as it does react consistently with important functions such as lockout being available from both switches. Other than that, the interface is reasonably well designed with good responsiveness, shortcuts such as lockout being accessible in the way many users will have muscle memory for, and reacting to the user in the way that is typically expected.

Using the Light

The HD01 is very small and light and disappears into all but the smallest pockets. Many people find a flat form factor less intrusive to carry than a cylindrical light as it can be easier to situate between different objects, and considering the HD01's relatively small size and weight, it is easily EDCable, either as a primary light or as a backup secondary light for someone who may carry it predominantly for the laser. The tailcap magnet is reasonably strong, although not the very strongest, and most metal surfaces allow the HD01 to attach stably and be easily repositioned without falling off. I am slightly disappointed I could not use the side LEDs with the laser, but the combination of the magnetic tailcap and laser allows for some interesting and fun applications such as creating a laser grid to crawl underneath.

The UI is clearly designed with concurrent use of the laser and main emitters, something the popular and competing Olight Arkfeld's UI has as a much clunkier operation to do compared to the seamlessness of the HD01 here, and I could see the HD01 being an excellent choice for people doing inspection or similar work who may need to both illuminate something and point out a specific area. The main LED is low CRI, so a high CRI option would likely be appreciated here, but overall the tint is reasonable and the beam contains relatively few artifacts. The laser does have some beam artifacts up close, but these disappear at a distance, and it is noticeably brighter than the Arkfeld, with reasonable visibility under normal lighting conditions, the dot only really being drowned out in strong sunlight.

Ergonomically, the HD01's finish is smooth and has a slightly slippery feel, but the pocket clip makes it easy to handle and it never slipped out of my hand entirely. Under normal use and testing it never developed any noticeable marks or scratches, although the TIR optic did pick up a couple of minor scratches from carrying. The HD01 fits well into my hand, although some users with very large hands may find it slightly short necessitating an adjustment of grip to operate the buttons.

The side LEDs are high CRI, and not quite as bright perceptually to me as on the IF24, but also appear to have a slightly nicer tint, possibly helped by the more heavily frosted diffuser. Similarly, the RGB modes are also slightly less bright, again likely due to the optic. Main emitter output is very good considering the small size of the light. Compared to the obvious competitor, the Olight Arkfeld Pro, the output appears slightly lower, but with a tighter and throwier beam and marginally nicer tint.

When run on turbo, the HD01 heated relatively rapidly to around 35-40 degrees, before starting to gradually level off in heating rate, reaching a maximum temperature of 51 degrees after 5 minutes.

As mentioned in User Interface and similarly to the IF24, there is no brightness control on the RGB modes, with just one fixed output level that is a little too bright to be comfortable up close, and usable for illumination of an immediate area or ambient mood lighting in a room, but not usable as a general purpose flood channel, and in addition, the red mode is too bright to be reasonably usable for preserving night vision up close, although works a bit better for this purpose at a medium distance. The white mode does work for general purpose indoor room lighting, with a very wide beam angle close to 180 degrees, possibly slightly less wide than the IF24's due to the smaller diffuser, but still wider than most other ultra-floody lights such as Emisar or Fireflylite mules.

The side LEDs' CCT is not specified, but these appear to be the same LatticePower LEDs that Sofirn used in the IF24, with a CCT of approximately 4500k and a CRI of 91. DUV is relatively neutral.

Driver and Emitters

Not much detail has been released on the HD01's driver, although given the small size and output drop with battery depletion, I would expect it is likely a linear regulator. The output from the main emitter is overall very good given the HD01's small physical size and battery capacity, and while I was not expecting completely flat regulation, the drop in output is reasonably small as the battery depletes until near the very end of the test runs. The laser seems to have very good regulation, and did not drop in power through the test run at all until it entered LVP and switched off. Most green laser diodes have a forward voltage of 4V or more, so with the consistent output and regulation point to a boost driver here.

The main emitter is a LatticePower HM, listed as 6000-6500k. This emitter and optic combination has a moderately throwy beam profile, with smooth spill with relatively few distinct artifacts other than two lines visible up close, and reasonably good tint consistency with only a slight band of yellow around the hotspot. CCT ranged from 6361k on moon to 7186k on turbo, with a relatively strongly negative DUV at all points - while I may be known for liking cool CCTs more than some people, I feel that most people will at least find the HD01's tint acceptable for a cool white LED.

For the side flood LEDs, the HD01 uses the same LEDs as the IF24, LatticePower CSP1313, but the ones in the HD01 read as closer to 4500k than the 5000k seen on the IF24 - this likely explains the lower output when compared to the IF24 if a lower CCT bin was used. I was able to confirm that the 90 CRI bin is again being used, and my sample measured at 91. The DUV is slightly positive - less positive than on the IF24, likely helped by the more heavily frosted diffuser, and the beam profile is almost as wide at close to 180 degrees, although very slightly less, likely due to the narrower diffuser. Overall, the flood LEDs are usable for up close tasks without much problem, and at the low output levels and with the CCT on the warm side of neutral, overall I feel some good tradeoffs were made here.

I measured the HD01's CCT and CRI with a Colormunki Photo and ArgyllCMS.

CRI and tint

Power and Charging

With a fixed nonreplaceable LiPo battery, built in charging is the only way to use the HD01. The charging port is protected by a rubber flap, which feels slightly loosely fit, and likely contributes to the poor IP rating.

The switch LEDs turns red when charging and green when the charge is completed. Charging works with both USB-A to C and C-C cables.

Charging data was collected using rd-usb with an RDTech TC66C (info, Amazon (US).

Moddability and Repairability

Two words: "Good luck!"

The only obvious point of entry into the HD01 is the tailcap, where a pry tool might be usable to gain access. The internal battery is presumably closest to the tailcap based on the rattle mine has when shaken, but access to the rest of the light such as the driver or emitters is likely to be difficult or impossible. If anyone has any teardown photos, I would be interested to hear about it so I can feature or link them.

Performance

All lumen measurements taken using a 4.5 inch Texas Ace lumen tube. Candela measurements were performed indoors at a distance of 3m, using a UNI-T UT383BT datalogging luxmeter.

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. I logged the value every second for the first 5 minutes, then every 5 seconds up to 30 minutes, then every 30 seconds past that point.

Output and Throw

Runtime

Laser Performance

I measured the laser's performance with a Sanwu Tracer - this meter is designed for significantly higher power levels than the HD01's spec of 5mW, and I did run into some difficulty in taking these measurements, as at this low power range, the reading is noticeably affected by changes in ambient temperature and even airflow near the test area. As such, I limited the test to a short runtime to collect accurate power figures, then did a separate test for overall runtime. I measured 2mW from the laser on the short run, while on the long run, the measured power figures were not accurate so I only took overall runtime - the HD01 was able to run the laser for a total of 16 hours continuously and when it entered LVP and the laser switched off, when switched back on it still read 2mW, showing excellent regulation on this channel.

Performance Overview

The main emitter does not use a particularly efficient driver, with output steadily dropping with battery level. I could not find a spec for the battery capacity anywhere so direct comparisons are difficult, but I would guess the driver uses a linear regulator. The laser, on the other hand, sustains its performance all the way from full to empty, with relatively little fluctuation in measured power at a steady 2mW, noticeably exceeding its runtime spec by 3 hours. ~1100lm is decent for a small light, with a balanced beam with perhaps a slight bias towards throw. Efficiency on the side LEDs is noticeably lower than the main LED, with a runtime of only 1 hour 19 mins on high. Throw was slightly better than advertised, and better than many other small flat lights such as the Arkfeld, and not that far off the Wuben X2.

Beamshots

HD01

Comparison Beamshots

HD01 Laser Beamshots

Competitors

Olight Arkfeld Pro: The natural competitor to the HD01 most people might think of (along with the older non-Pro Arkfeld, which lacks the UV mode). Very similar squarish form factor (the Arkfeld is slightly longer and heavier), single LED plus green laser. The Arkfeld Pro lacks the HD01's side LEDs, but instead has a UV emitter, although the UV itself is made less useful by the absence of a ZWB filter. The Arkfeld's laser is noticeably less powerful than the HD01's, but the main emitter is slightly brighter and floodier. Both have built in nonreplaceable batteries, although the Arkfeld uses Olight's proprietary magnetic charger instead of USB. In my opinion, the HD01 has an overall better UI, and in particular is much nicer to use the laser and main emitter together, but the Arkfeld's is simpler to use and learn. The choice between the HD01 or Arkfeld is likely to come down to if you would prefer UV or high CRI flood/RGB LEDs, as well as how much laser performance you need.

Sofirn IF24: Significantly larger, replaceable battery, similar side LEDs with more modes and marginally higher brightness. Brighter main emitter but less nice beam. User interface is overall somewhat less usable, but has a better interface for the RGB modes.

Skilhunt Mix-7: The Mix-7 is an alternative choice for a light with both RGB and white emitters, as well as a magnet. The Mix-7 has a larger diameter than the HD01 but is overall smaller. While the Mix-7 usually would be considered weak in capacity and runtime with its 18350, it still compares positively to the HD01's built in battery. Significantly more powerful main emitters, combined with RGB that is less floody and more of a balanced beam, although despite the name, there is no way to actually mix the RGB; you get red, green, or blue, so it depends strongly on what you want the RGB mode for.

Wuben X1/X2, Nitecore EDC27: If the flat form factor is the main thing you are looking for, but the HD01 or Arkfeld are too small and low powered, these are some of the best flat lights around for overall performance. Significantly larger, main LEDs only, but with much higher overall main LED performance.

This section does not list all possible alternatives, is subject to my own interest and views on listed lights, and is primarily intended to give a general overview. A light not being included here does not mean it should not be considered a viable alternative.

Potential Improvements

Trying out a new section here: How I would improve the design of a light. No, I'm not going to say "Anduril and an extra 10,000 lumens" every time, even if that would improve every light ;) - these are intended to be small design changes that could be made while keeping the overall focus of a light.

• 14500 battery: Many enthusiasts dislike built-in batteries, and for good reason. All rechargeable lithium batteries eventually wear out. It leaves the user reliant on either the manufacturer, or the community to provide support when that happens. Some people will argue that even with heavy use, you can get 2-3 years from a battery, but ultimately, I object to this on planned obsolescence and environmental responsibility grounds. The HD01 is large enough that two 14500 cells should be able to fit inside (and even if it needed to grow a little, it is smaller than its main competitor as it is), and USB charging is already integrated, so the cells could be *semi-*replaceable if needed, similarly to the Wuben X1 - doable, but not something you'd want to do every day.
• Better RGB modes: The IF24 has additional RGB modes that are not present on the HD01. These could be added, in addition to reversible RGB ramping.
• Optics - the laser has a few beam artifacts that could be improved, while the main emitter has a bare TIR that will pick up scratches much more easily than a glass lens.
• LED: The LatticePower HM was presumably chosen for output. In general, for a small light, this is probably a good choice, but enthusiasts would still be happy to trade some output for a high CRI version with 519A, or possibly even a throwy version with a slightly lower CCT with an Osram W2 (CSLPM1.TG) while still retaining comparable output.

Final Thoughts and Score

The HD01 is available from wurkkos.com, and Wurkkos' official AE store. Atthe time of writing, it is currently available for $50 on Wurkkos.com, with an aditional 20% off for buying two or more using the discount code SPRING20.

As always, feedback is welcome - 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.