Contents

• The Boring Stuff
• What comes in the box?
• Design & Construction
• Size & Measurements
• User Interface
• Modes, Brightness & Throw
• Runtime & Currents
• Driver & Regulation
• Emitter & Beam
• Switch
• Carry & Ergonomics
• Batteries & Charging
• Competition
• Conclusion

The Boring Stuff

I purchased this light with my own money from Killzone Flashlights at full price back in late 2020. Here is the official product page but you can also get it on Amazon.

There are quite a few H04 variants. The base models are H04 (beaded TIR optic), H04R (orange peel reflector), and H04F (orange peel reflector with a flip-down diffuser). Additionally, if it has “RC” tacked onto the end, that means it comes with magnetic USB recharging and an upgraded headband. If it has “Mini” tacked onto the end, it’s a shorter body tube designed for an 18350 battery instead of 18650.

I only recommend H04 RC and H04 RC Mini, depending on the size you want. The better headband is worth the upgrade to an RC model, even if you don’t need the integrated charging. The other optic/reflector variants have uglier beam profiles and the flip-down diffuser on H04F causes glare.

What comes in the box?

• The light itself
• Pocket clip
• Headband (disasembled)
• Manual
• Extra o-rings
• Spacer to replace the tailcap magnet
• Lanyard
• Charging cable

Design & Construction

The design is great for a right-angle headlamp. I prefer this style, where the head is in-line with the body and the switch is on the side of the head. I tried Fireflies Pl47g2 which has a lopsided head and the button on the top, and I don’t like that style as much.

Build quality is excellent. The anodizing is thick, even, and smooth, but not glossy. The tailcap threads are square-cut, anodized, lubricated, and smooth. Only the tailcap is removable, but it’s o-ring sealed. Technically the “bezel” can be removed too but it’s kind of fiddly with four T5 torx screws that like to get lost.

Size & Measurements

From left to right:
Fireflies E07x Pro
Skilhunt H04 RC
Fireflies PL47g2
Emisar D4V2
Noctigon KR1

Measurement	Measured (mm)
Bezel Opening Diameter	15.3
Length	101.5
Switch Diameter	10.0
Switch Proudness	1.6
TIR Diameter	17.0
TIR Thickness	9.7
MCPCB Size	Unable to measure
Body Tube Diameter (internal)	19.0
Body Tube Diameter (mode)	21.9
Ride Height (sticking out of pocket)	17.1
Pocket Clip Space (for pants material)	2.2
Pocket Clip Space (at mouth)	4.1
Pocket Clip Width	6.5
Pocket Clip Thickness	0.9
Pocket Cip Slot Width	4.4
Pocket Clip Slot Diameter	20.6
Tailcap Diameter	23.6
Tailcap Length	12.5
Driver Diameter	Inaccessible

Weight without battery: 54g / 1.90oz
Weight with battery: 100g / 3.53oz
Weight with battery & headband: 149g / 5.26oz

User Interface

UPDATE: SKilhunt has changed the UI since I wrote this review. New H04 RC samples have the same UI as H300. The rest of this UI section is now outdated.

The user interface has a little extra fluff you don’t need, but it’s fine. I wish it were Anduril 2, of course. It defaults to mode group A which uses sub-modes and hold for off, which is a no go. If you buy one, just hold the button down for several seconds right when you get the light to switch to group B, and then never worry about it again. I’ll detail group B below.

The actions are # of presses followed by a hold (H) or a release (C). So, “1C” is one click and release. “2H” is two clicks but you hold down the last one. Here’s group A.

State	Action	Result
Off	1C	On (mode memory)
Off	1H (short)	Moonlight (memorized)
Off	1H (long)	Lockout
Off	1H (longer)	Switch to group A (don’t)
Off	2C	Turbo (not memorized)
Off	3C	Blinkies (mode memory)
On	1C	Off
On	1H	Next Mode (low-high direction)
On	2C	Turbo
On	3C	Mode Configuration*
Lockout	1C	Moonlight blink
Lockout	1H	Unlock to Moonlight
Blinkies	1C	Off
Blinkies	1H	Does nothing
Blinkies	2C	Next Blinky Mode (strobe-beacon 1-beacon 2)

Mode configuration allows you to enable or disable up to 6 of the 7 normal modes. You must always have at least one, plus Turbo. When you enter mode configuration, the light will turn on and start slowly cycling up through the modes. If the mode is enabled, the switch will glow red. If the mode is disabled, the switch will not glow. Hold to exit configuration mode and save your changes. Click 3x to exit reset to factory mode settings.

Lockout makes the switch LED will blink red periodically. This mode creates a lot of parasitic drain, so I recommend using mechanical lockout (unscrewing the tailcap) instead of electronic lockout.

The one problem I have is the way lockout is accessed. A long hold for lockout is a bad solution because it’s the second-most-likely action to happen by accident (besides a click of course). This electronic lockout is not all that likely to prevent accidental activation in a bag or pocket. Fortunately, mechanical lockout works great. I’m also used to Anduril, which turns on and ramps up via a hold from off. I find myself regularly putting H04 RC into lockout when I’m trying to get it to turn on moonlight and start increasing brightness, and that can get annoying.

Modes, Brightness & Throw

Disclaimer: Lumen measurements were taken on a Texas Ace 3.5″ Lumen Tube. A candela measurement was taken with an Opple Light Master III on the highest brightness, and other candela figures were calculated relative to that. Runtime tests were performed with the Ceilingbounce app on my smartphone. All of these tests were performed with a fully charged Samsung 30Q battery unless otherwise specified. I cannot measure moonlight directly, so moonlight readings are calculated based on the brightness relative to the next-lowest mode.

Level	Lumens (@ Turn-On)	Candela (@ Turn-On)	Throw (meters)
T1 (Turbo)	550	1,800	85
T2	372	1,217	70
H2	106	347	37
M2	18	59	15
L2 (Moonlight)	0.37	1.2	2.2

Why those modes? H04 RC’s user interface allows you to activate or deactivate any mode except maximum Turbo (T1). The modes you see above are the ones I find that I like to use.

Mode Spacing: Mode spacing is pretty good between all 8 modes. You can activate/deactivate whichever ones you want to get whatever mode spacing you want.

How does it compare to the official specs? The official specs are for the low CRI, cool white emitter option so this Samsung LH351D version does not meet the official specs. This performance difference is about right though, so nothing weird is going on.

Runtime & Currents

T1: starts out at 550 lumens and stays there for 2.5 minutes, then drops to a little over 400 lumens. It stays there until just before the 1.5 hour mark where low voltage stepdown begins. It takes just under an hour to go from ~400 lumens to off, with some low voltage warnings in there and a low voltage shutoff at the end.

T2: starts out at about 370 lumens and steps down a little bit over the course of 15 minutes to 350 lumens. It then stays there until just after the 2 hour mark, where low voltage stepdowns begin. I ended this test before low voltage warnings or shutoff could occur.

H2: is a perfectly flat 106 lumens for about 11 hours before low voltage warnings kick in. It shuts completely off at 11 hours and 30 minutes.

LVP: I observed both a low voltage warning, and low voltage protection (shutoff).

Current: I’m not equipped to do extreme duration runtime tests or extremely high current measurements. I only measure the currents on low modes and I calculate the estimated runtime of those modes based on the capacity of the battery or batteries I’m using for testing.

Level	Current @ Tailcap (milliamps)	Estimated Runtime
M2	~50	60 hours
L2 (moonlight)	5.49	23 days
Standby (parasitic drain)	0.041	8.4 years
Lockout (parasitic drain)	3.7-4.5	~1 month

Driver & Regulation

I don’t know much about the driver here. It’s held in place between the head and body tube, which are glued together.

Regulation is OK. The Turbos are affected by battery voltage, but the other modes I tested are not.

Note: All regulation measurements are taken at turn-on so they do not reflect any thermal or low voltage stepdowns that may occur.

Thermal regulation: There is no thermal regulation present, but there is a timed stepdown from T1. Heat has not been an issue for me in the last year of use.

PWM: Neither my eyes nor my Opple Light Master III could detect any PWM.

Emitter & Beam

H04 RC is offered with a few emitter options, but the one you should get is the High CRI Samsung LH351D option. Mine happens to be a 4000K because I bought it last year, but they’ve changed to using all 5000K now. It’s not the brightest thing, but the color is much better than any of the other emitter options. The tint on mine is a little bit green, but I’m not sure what the tint is like in the newer 5000K samples.

The beam is nice and floody with a very smooth transition from hotspot to spill. The spill slowly fades out to nothing and it’s pleasant to use because there aren’t any hard edges in the beam. This is the perfect beam pattern for a headlamp. There’s some tint-shift in the photo above, but I think that’s a camera artifact because I can’t detect any by eye.

When bouncing the light around in my white photo booth, I measured CCT at 3800K and RA (CRI) at 94 with my Opple Light Master 3. The beam shots below were taken with the exposure adjusted for high output hotrod lights. In real life, the 550 lumens from H04 RC feels a lot brighter. Importantly, H04 can maintain a higher brightness than all the other lights in these beamshots, and sustained brightness is much more important for a headlamp than Turbo brightness.

Outdoors the beam is plenty bright, especially on Turbo. I find myself using H2 and T2 most frequently. If I’m using H2, it’s really easy to quickly double tap the switch up to T1 for some extra brightness, then a quick double tap again jumps back to the mode I was using before. I love that feature.

Moonlight & Tint Comparison from left to right:
Skilhunt H04 RC | LH351D 4000K
Noctigon KR4 2-channel | Nichia 219B SW27/SW45K Mix
Emisar D4V2 | SST20 4000K
Wurkkos WK02 | SST20 4000K
Noctigon KR1 | Osram W1

Moonlight is a nice, low, 0.37 lumens. It won’t cause any problems with night vision preservation. The tint on mine is a little green, but I’m not sure what it’s like on the newer 5000K models.

Switch

The switch is electronic and located on the side of the head. I significantly prefer this switch placement on a right angle light, as opposed to having the switch on the top of the head. It makes actuating the switch much easier while the light is mounted in the headband. The top switch is better for handheld use though.

This switch has a partially transparent rubber boot that allows light through a red LED indicator underneath. It blinks right after the light is turned on to indicate battery status. Each blink represents 25% capacity, so one blink is 0-25% and four blinks is 75-100%. The indicator is also used in mode configuration to tell you which modes are active or not.

Carry & Ergonomics

It’s a little bit fiddly in hand, but it’s perfectly usable. The switch is a little bit awkward to use handheld because it’s on the side of the head, but it’s not too bad.

H04 RC carries fine in-pocket. It’s compact and light weight so it doesn’t get in the way of anything. The stock clip is OK, but I prefer to use a slightly modified Convoy Universal Clip for deeper and head-down carry. It works fine un-modified, but it’s a little more secure with some fitment.

The other way to carry H04 RC is with the fantastic headband. This headband has two stand-out features: the top strap is removable, and you can clip the light in place without removing the pocket clip! Most headbands use chincy rubber loops to hold the light in place, and they make it difficult to insert or remove your light from the headband, and they don’t allow for the pocket clip to be installed. This Skilhunt band has a plastic and rubber clip that holds the light securely and allows the clip to stay installed. If it’s not secure enough for you, you can stretch one of the included o-rings over the front of the headband clip to really lock the light into place. There’s a bead of silicone along the inside of the band for extra grip, and the outside is lined with reflective markings to make you easily visible from behind. I want every right angle light to use this headband. If you’re interested in that little hair-tie headband keeper trick I’m using, I made a short YouTube video about it.

The magnet in the tailcap is not the strongest I’ve seen but it does the trick. It can hold the light up on a vertical surface. It can also be removed and replaced with a plastic spacer, by pulling the spring out of the tailcap temporarily.

Batteries & Charging

H04 RC accepts a wide variety of batteries, the widest variety I’ve seen in any light that I can recall.

• 1×18650
• 2xCR123A
• 2×16340 (button tops)
• 2×18350 (button tops)

A battery may or may not be included, depending on where you buy from and what options you select. I tested mine with a flat top, unprotected, Samsung 30Q. The current requirements are not high, there is low voltage protection, and there are springs on both ends, so virtually any variant of the above cells can be used. I recommend a ~3500mah 18650 for the most runtime, but battery selection will not meaningfully affect the light’s brightness.

Charging is facilitated by a magnetic charging contact on top of the head, and an included corresponding magnetic USB charging cable. This is the easiest charging solution I’ve seen for daily recharging, and it doesn’t introduce any water ingress concerns either. It does mean you’ll need to bring the proprietary cable or an external charger with you on trips though.

Competition

Here are some lights in the same class and how they compare.

Sofirn SP40A LH351D: cheaper, brighter, same LED, narrower beam, worse headband, heavier, standard micro-USB charging instead of magnetic, worse clip, short tube included, worse UI, no moonlight, much worse regulation, includes thermal management, different switch location

Armytek Wizard C2 Pro Nichia: very similar overall, just a mild upgrade in a few ways (brightness, driver, durability) at a higher price. The extra cost isn’t justified for most users.

Zebralight H600Fc MK IV: worse headband, no integrated charging, no magnet, different user interface, warmer CCT, lighter, better driver, different switch location, more durable, more expensive

This section is not comprehensive. If I didn’t include a particular light here, it doesn’t mean it’s bad or doesn’t deserve to be here. I simply cannot list every possible competitor.

Conclusion

I think H04 RC is the best headlamp on the market. With its right-angle design, pocket clip, magnetic tailcap, and excellent headband it’s extremely versatile. Skilhunt put money where it matters for most users (great design, good user interface, integrated charging, nice beam) without wasting any on features that most users won’t need (extreme efficiency, extreme durability). If you’re in the market for a good, general purpose flashlight/headlamp combo, this is it.