Contents

• Pricing & Availability
• What comes in the box?
• Design & Construction
• Size & Measurements
• User Interface
• Mode Chart
• Runtime
• Driver & Regulation
• Emitter & Beam
• Switch
• Carry & Ergonomics
• Batteries & Charging
• Competition
• Conclusion

Pricing & Availability

Sofirn sent me this light in exchange for an honest review. Here is the official product page and the Amazon page where you can see current pricing. It’s very affordable.

What comes in the box?

The packaging is minimal. It’s just a simple cardboard box that says Sofirn. The manual is even printed on letter paper, not the glossy paper you usually get. It keeps the cost down. The following items are included in the box:

• The light itself
• Battery (inside the light)
• Headband
• User manual
• Micro-USB cable

Design & Construction

The design looks like a pretty typical headlamp. I asked Sofirn why it says “77outdoor” on top and they said that’s another spin-off brand like CSTEBOKE.

Build quality is sub-par from Sofirn, but still fine overall. The threads are a little shallow, unlubricated and overall the machining isn’t quite as nice as most of Sofirn’s other work. I applied some super lube to the threads and it solved the grittiness. Even with all that it’s still going to be higher quality than anything you find at a big box store for the same price.

Size & Measurements

Skilhunt H04 RC | Emisar D4V2 | Emisar DW4 | Sofirn D25LR | Lumintop FW3A

Measurement	Measured (mm)
Height	24.3
Width	85.8
Depth	35.6
Switch Diameter	~14.5
Switch Proudness	0.0
Body Tube Diameter (internal)	19.5
Tailcap Diameter	24.8
Tailcap Length	15.6
Included Battery Length	67.2
Included Battery Diameter	18.6

Weight with headband & included battery: 122g

User Interface

There are no shortcuts. There are no double or triple clicks. There are no blinky modes. The UI is simple and it works.

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.

State	Action	Result
Off	1C	On (white, mode memory)
Off	1H	On (red, mode memory)
On (either color)	1C	Off
On (either color)	1H	Cycle brightness (moon > low > med > high>

Mode Chart

Disclaimer: All measurements taken at turn-on. Lumen measurements were taken on a Texas Ace 3.5″ Lumen Tube. A candela measurement was taken at 10 meters with an Opple Light Master III on the highest brightness, and other candela figures were calculated relative to that. CRI, CCT, & DUV data was taken for each mode from a few feet away at the center of the hotspot with the Opple Light Master and Waveform DUV Calculator. Runtime tests were performed with the Ceilingbounce app on my smartphone. All of these tests were performed with a fully charged MODEL battery unless otherwise specified. I cannot measure moonlight directly, so moonlight readings are calculated based on the brightness relative to the next-lowest mode. None of this is professional equipment, so take all of these measurements with a grain of salt.

Above are the official specs, followed by my own measurements below.

Level	Lumens	Candela	Throw (Meters)	CRI (Ra)	Color Temp. (K)	DUV (Tint)
High	590	700	53	97	4680	0.0024
Medium	310	368	38	95	4680	0.0042
Low	56	66	16	95	4660	0.0052
Moonlight	2	2	3	96	4570	0.0041

Mode Spacing: is OK. Medium and High are a little close together.

Runtime

Performance: Is not bad. High modes last 1 minute before stepping down, and “stable” brightness starts at a respectable 300 lumens. There’s a downward trend for every runtime though, which indicates an unregulated FET driver.

Thermal regulation: appears to be present and functional. The light never gets uncomfortably hot.

LVP: is present and works well. Both low voltage warnings and low voltage shutoff are present, as it should be.

Driver & Regulation

I wasn’t able to get a photo of the driver because it’s buried. Based on the downward drift in the runtime tests it’s clear that this is an unregulated FET driver, so I didn’t do any separate regulation testing. A FET driver is just fine at this price point.

PWM: is present on all modes except high but it’s quite fast so it’s not visible, audible, nor detectable by my phone camera. Unless you have testing equipment you’d never know.

Parasitic Drain: I did multiple tests just to be sure, but I measured 1 microamp or less of parasitic drain. That’s nothing. For comparison, most e-switch lights have somewhere around 20-40 microamps of parasitic drain.

Emitter & Beam

There are two emitters: 1 white Samsung LH351D in 5000K, and a red Luminus SST20. Both of these are good choices, especially the SST20. It’s a deeper red than most other red emitters on the market.

Both beams are nice and artifact-free. The hotspot from the white beam is a little wider

In the beamshots above, the trees where I’m aiming the hotspot are 175M away. In the beamshots below, the park bench where I’m aiming the hotspot is 42M away.

Switch

The switch is located on the side and it sits under a green GITD rubber boot. It’s an e-switch and is very clicky. Placing it on top of the light instead of the side would make it a little easy & ergonomic to use, but the placement is not bad. It’s a fine switch overall.

It’s possible to access the switch by loosening the retaining ring with snap ring pliers, if you ever want to repair or modify it.

Carry & Ergonomics

D25LR includes a simple headband that only goes around your head, not over the top with an extra strap. I think that’s great because those top straps are uncomfortable and cumbersome. I wore D25LR on several occasions for up to an hour and it never got uncomfortable. It might be a little bit heavy for running, but for all other activities it should be just fine.

It’s held in the headband by a large plastic mount that works well. It ratchets up and down for angle adjustment and stays in place firmly.

If you want to remove it from the headband and use it as a right angle light, you can do that. Holding it is a little weird but it will tailstand just fine. There’s no pocket clip, magnet, or lanyard included for handheld use.

Batteries & Charging

Sofirn includes a 3000mah unprotected 18650 cell and it’s perfectly adequate. Unprotected flat tops work just fine too. Protected button tops may be hit or miss though as they can vary in length and I’m not sure all of them will work. The protected cell from Thrunite (known for weirdly long protected cells) I have on hand at the time of writing is too long to fit.

Charging is facilitated by a micro-usb port hidden on the switch-side. There’s a collar there which you can unscrew to reveal the charging port. This is a robust solution that should provide better durability and water resistance than a rubber flap port cover.

The light is fully functional when plugged in, so you could even charge it while it’s on your head for extended runtime. It’ll even work without a battery, just not on high mode.

Competition

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

Wurkkos HD15R: right-angle style, top strap, magnetic tailcap, pocket clip, USB-C charging, powerbank function, same LED’s, more feature-rich & complex UI, multiple body colors, more expensive, only available from China, similar unregulated driver, same 18650 battery

Sofirn HS10: smaller, lighter, white-only, similar unregulated driver, smaller 16340 battery, USB-C charging, similar price, ships from China, also available on Amazon with fast shipping for a higher price

Emisar DW4: regulated linear driver, many LED options, larger & heavier, optional 18350 body, advanced Anduril 2 user interface, no integrated charging, RGB aux LED’s, much 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

At the time of writing, I think this is the best budget headlamp available. It’s comfortable, easy to use, bright enough, decent quality, includes a battery, is USB rechargeable, and it’s readily available on Amazon.

Thanks to Sofirn for sending me this light for review!