Sofirn ST2 Multi-Function Flat Flashlight Review
The Sofirn ST2 multi-function flat flashlight features white, red, and UV output and runs two standard 18650 cells (included) and a ramping interface. Read on!
Official Specs and Features
Here’s a link to the Sofirn ST2 multi-function flat flashlight product page.
Versions
There’s just one version of the Sofirn ST2 multi-function flat flashlight.
Price
The introductory price of the Sofirn ST2 multi-function flat flashlight is $62.99, with an MSRP of $109.99.
What’s Included
- Sofirn ST2 multi-function flat flashlight
- Charging cable
- Lanyard
- Manual
Package and Manual
Build Quality and Disassembly
The Sofirn ST2 multi-function flat flashlight has a solid and good build quality. But it also has an interesting design. The head rotates from putting light forward to 90 degree output.
Yes, twist lights already exist, but this is one of the more solid implementations of this feature.
Initially, it would seem like this light doesn’t come apart, but the tailcap does come off. Just two T6 TORX screws hold this tailcap on. The tailcap magnet does complicate getting the screws back in, but it can be managed.
The positive contact are just buttons. More about these cells later.
Size and Comps
113mm x 46.3mm x 22mm and 248g
Here’s the light in hand:
Here’s the test light with the venerable Convoy S2+. The version below is a custom laser-engraved Convoy S2+ host by GadgetConnections.com. I did a full post on an engraved orange host right here! Or go straight to GadgetConnections.com to buy your Convoy S2+ now!
Also in the photo above, my Standard Reference Material (SRM) flashlight is the Hanko Machine Works Trident, an 18350 light. While I have not reviewed or tested the Gunner Grip version seen here, I have tested a Hanko Machine Works Trident Total Tesseract in brass. I love the Trident, and it’s a striking contrast to the inexpensive Convoy S2+, another great SRM.
Retention and Carry
The Sofirn ST2 multi-function flat flashlight ships with a beefy belt clip installed.
There’s also a lanyard. The only place to attach the lanyard is the belt clip.
The tailcap has a strong magnet, too.
Above, you may note a new holder for my magnetic-tailcap items. That’s the Exceed Designs Hyzer Titanium Mini Hatchet D2 axe. The handle (as the name suggests) is titanium. But the blade is D2 steel and perfect for retaining magnetic tailcap flashlights! The Hyzer is available in a bunch of cerakote body colors as well as different thickness D2 heads.
Power and Runtime
The Sofirn ST2 multi-function flat flashlight is powered by two 3800mAh 18650 cells. These are standard flat-top cells , and while not meant for changing in the field, they absolutely are accessible (and not soldered or anything else). So this is a nice feature!
Both cells go into the light with the positive end toward the head. This should mean they’re in parallel and that the light will work from just one cell, but I did not test that.
The Sofirn ST2 multi-function flat flashlight claims 3000 lumens, and even at startup, I don’t see 3000 lumens. The light does hold initial output for a respectable amount of time, though (around a minute) before stepping down dramatically to around 500 lumens.
The temperature lines in these charts are included as general context, not precise measurements. The values represent the range (min to max) during testing, but should not be taken as exact readings. A temperature sensor is not always attached to the bezel (or even the hottest spot, assuming that could be defined). Even with ideal placement, too many variables affect temperature to definitively state a specific max value.
Charging
The Sofirn ST2 multi-function flat flashlight charges via USB-C. The charge port has a press-in cover.
Sofirn includes a USB-C to USB-C cable.
Charging works fine and is reasonably quick, at around 4 hours. C to C and A to C work equally great.
Modes and Currents
| Mode | Mode Claimed Output (lm) | Claimed Runtime | Measured Lumens |
|---|---|---|---|
| Turbo White | 3000-650 | 1m+5h28m | 2482 (0s) 2304 (30s) |
| Low White | 5 | 430h | 5 |
| Turbo Red | 130-70 | 3m+7h30m | – |
| Low Red | 1 | 430h | – |
| High UV | 1240mW | 7h | – |
| Low UV | 400mW | 27h | – |
Pulse Width Modulation
Neither of the steady white LED modes use PWM.
Click here to see a “baseline” – a chart with almost no light hitting the sensor.
Then there’s the Ultrafire WF-602C flashlight, which has some of the worst PWM I’ve seen. It’s so bad that I used a post about it to explain PWM! Here are multiple timescales (10ms, 5ms, 2ms, 1ms, 0.5ms, 0.2ms) to make comparing this “worst” PWM light to the test light easier. That post also explains why I didn’t test the WF-602C at the usual 50us scale.
User Interface and Operation
The Sofirn ST2 multi-function flat flashlight is controlled first by a selector switch with three positions. After that, control is by the indicating e-switch, seen below, indicating in orange.
The rotary has three positions, in this order: Red, White LED, and UV (UV is selected above).
Here’s a user interface table!
| State | Action | Result |
|---|---|---|
| Off | Click 4x | Lockout |
| Lockout | Click 4x | Unlock to mode memory |
| Lockout | Click | White LED Blink 2x to indicate lockout |
| Off | Click | On in mode memory of selected output |
| On | Click | Off |
| Off | Hold | Low of selected output |
| Unlocked, off | Double click | Turbo of selected output (or High UV) |
| Turbo | Double click | Low |
| Unlocked, off | Triple click | Strobe group. White: Strobe Red: Double blink |
| Strobe group | Double click | White: Strobe advance: Strobe > SOS > Beacon Red: (No change, there is only one red blinky output) |
| White or red on | Hold | Ramping up (initial hold) or down (after releasing and reapplying hold) |
| UV on | Hold | Iterate between UV high/low |
LED and Beam
The white LED is a Luminus SFT-42R, and Sofirn says it’s 6500K. It has a small reflector.
LED Color Report (CRI and CCT)
Even on turbo, the output is not quite as cool as 6500K. CRI is low.
CCT (Correlated Color Temperature) refers to the measurement of the color appearance of light, expressed in Kelvins (K), which indicates whether the light is warm (yellowish) or cool (bluish). A lower CCT (below 3000K) is considered warm light, while a higher CCT (above 5000K) gives cooler, bluish light.
CRI (Color Rendering Index) is a measure of how accurately a light source renders colors in comparison to natural sunlight. Scored on a scale from 0 to 100, higher CRI values indicate that colors appear more true to life and vibrant, similar to how they would look under the sun.
Beamshots
These beamshots always have the following settings: f8, ISO100, 0.3s shutter, and manual 5000K exposure. These photos are taken at floor level, and the beam hits the ceiling around 9 feet away.
Tint vs BLF-348 (KillzoneFlashlights.com 219b version) (affiliate link)
I keep the test flashlight on the left and the BLF-348 reference flashlight on the right. These photos are taken around 18 inches from the door.
I compare everything to the KillzoneFlashlights.com 219b BLF-348 because it’s inexpensive and has the best tint!
Summary and Conclusion
First and foremost, I appreciate that it is possible to swap the cells on this light and that they are standard. I dislike very strongly that the Sofirn ST2 multi-function flat flashlight offers only ramping. As for generally using the light, it’s fine. The build quality is good, and the current price is reasonable.
The Big Table
| Sofirn ST2 multi-function flat flashlight | |
|---|---|
| Emitter: | Luminus SFT-42R (Cool white) |
| Price in USD at publication time: | $62.99 |
| Cell: | 2×18650 |
| Runtime Graphs | |
| LVP? | Probably |
| Switch Type: | E-Switch |
| Quiescent Current (mA): | ? |
| On-Board Charging? | Yes |
| Charge Port Type: | USB-C |
| Charge Graph | |
| Power off Charge Port | Yes |
| Claimed Lumens (lm) | 3000 |
| Measured Lumens (at 30s) | 2304 (76.8% of claim)^ |
| Candela per Lumen | 10 |
| Claimed Throw (m) | 270 |
| Candela (Calculated) in cd (at 30s) | 883lux @ 5.144m = 23365cd |
| Throw (Calculated) (m) | 305.7 (113.2% of claim)^ |
| Claimed CCT | Cool white 6500 |
| Measured CCT Range (K) | Cool white 6000-6400 Kelvin |
| Item provided for review by: | Sofirn |
| All my Sofirn reviews! | |
^ Measurement disclaimer: Testing flashlights is my hobby. I use hobbyist-level equipment for testing, including some I made myself. Try not to get buried in the details of manufacturer specifications versus measurements recorded here; A certain amount of difference (say, 10 or 15%) is perfectly reasonable.
What I like
- Good build quality
- Tilt head does not feel cheap
- Cells are accessible
- Cells are standard flat-tops
- Hits the throw claim
- Red has ramping too (by that I mean: many output levels of red, but I still wish they were stepped)
What I don’t like
- Ramping only
- UV (but at least it’s easy to avoid!)
- Misses (dramatically?) the output specifications
- No powerbank option? I don’t see it on the product page… Seems like a natural feature of this light.
Notes
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