Sofirn SR15 Rechargeable Flashlight Review
The Sofirn SR15 rechargeable flashlight has four Luminus SFT25R emitters. This achieves fantastic throw and high output. It runs a 21700 and has USB-C charging.
Official Specs and Features
Here’s a link to the Sofirn SR15 rechargeable flashlight product page.
Versions
There’s just one version of the Sofirn SR15 rechargeable flashlight.
Price
MSRP of the Sofirn SR15 rechargeable flashlight is $75.99 but there’s currently a coupon or two. All the discounts bring the Sofirn SR15 rechargeable flashlight price down to $46.99. That includes the 21700, too.
The Sofirn SR15 rechargeable flashlight is available on amazon.com, too! It lists at $55.99 but there’s a 30% off coupon. Buy the Sofirn SR15 rechargeable flashlight with my referral link!
What’s Included
- Sofirn SR15 rechargeable flashlight
- Sofirn 5000mAh 21700
- Lanyard
- Charging cable
- Spare o-rings (2)
- Manual, etc.
Package and Manual
Build Quality and Disassembly
The build quality is fine. There’s nothing bad to say here. I appreciate the “flashlighty” look of the Sofirn SR15 rechargeable flashlight!
Both the head and tail have thick springs.
I was unable to remove the tailcap – it might be glued to the cell tube. The head threads are anodized and well-lubed.
Size and Comps
Size: 40mm x 130mm
Weight: 128g (without battery)
If the flashlight will headstand, I’ll show it here. If the flashlight will tailstand, I’ll also show that here too!
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!
In the photo above, you may note that the SRM (standard reference material) flashlight for comparison has changed! I used a TorchLAB BOSS 35 for ages. Now what you can see as the 18350 SRM is the Hanko Machine Works Trident. 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 next to the inexpensive Convoy S2+, which also makes a great standard reference material.
Retention and Carry
A friction-fit pocket clip is included. The clip is a one-way type and there’s a hole where a lanyard can be attached.
In the tailcap is a magnet which is plenty strong for holding the Sofirn SR15 rechargeable flashlight in place.
Another place to install the lanyard is through this hole in the tailcap.
The lanyard is very basic.
Power and Runtime
Sofirn includes a flat-top 21700 lithium-ion cell for use in the Sofirn SR15 rechargeable flashlight.
The cell goes with the button toward the head. Note how much the cell sticks out of the light. You have to squeeze the head and body together (depressing both springs a bit) with a purpose to get the threads started.
If you forget that, you can check the little printed cell orientation icon on the tailcap.
Below are a few runtime tests. The light does not hit the claimed 4500 lumens. After the stepdown, output is steady at around 600 lumens. That’s respectable and also will provide a good bit of throw due to the beam profile.
Low voltage protection was observed in every test and the switch will also indicate the power level (as follows):
Green: 70-100% power
Red: 30-70% power
Red flashing: 1-30% power
Charging
Charging is built in. There’s a USB-C port in the head. This port has a press-in cover.
A USB-C to USB-C charging cable is included, too.
Below you can see a C to C and A to C charging test. They’re both fine – but C to C seems markedly faster, charging at over 3A at points during the cycle. A to C maxed at 2A.
While charging, the switch is red. When charging is complete, the switch turns green.
Modes and Currents
| Mode | Mode Claimed Output (lm) | Claimed Runtime | Measured Lumens | Tailcap Amps |
|---|---|---|---|---|
| Turbo | 4500-1000 | 1m+2h | 3006 (0s) 2733 (30s) |
11.80 |
| High | 1500-1000 | 3m+2h30m | 1559 (0s) 1459 (30s) |
5.55 |
| Medium | 500 | 5h30m | 627 (0s) 590 (30s) |
1.86 |
| Low | 70 | 17h15m | 84 | 0.39 |
| Moonlight | 1 | 410h | 0.24 | [low] |
Pulse Width Modulation
There’s really no PWM here, which is great!
Here you can 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 SR15 rechargeable flashlight is controlled by a single indicating e-switch.
Below you can see the switch indicating in green.
Here’s a user interface table!
| State | Action | Result |
|---|---|---|
| Off | Click | On (Memory) |
| On (Except Turbo) | Click | Off |
| On | Hold | Stepped Group: Mode advance (L>M>H) Ramping Group: Brightness increase. (Release and repress for brightness decrease) |
| Off | Hold | Moonlight |
| Any | Double click | Turbo |
| Turbo | Click | Return to the previous mode |
| Turbo | Double click | Moonlight |
| Any | Click 3x | Strobe |
| Strobe | Click | Return to the previous mode |
| Strobe | Double click | Strobe advance (SOS> Beacon> Strobe) |
| On | Click 4x | Iterate between ramping and stepped^ |
| Off | Click 4x | Iterate lockout |
| Lockout | Click | Blink twice to indicate lockout |
| Lockout | Hold | Momentary moonlight |
^ The manual doesn’t actually cover the ramping output. It’s pretty basic, though.
LED and Beam
Sofirn is using the Luminus SFT-25R emitter in the SR15 rechargeable flashlight. And there are four of those emitters! It’s a cool white option, stated at 6000K-6500K. Each has a part of a reflector.
Throw is quite surprising out of this quad-emitter light, though. The beam profile is quite tight!
LED Color Report (CRI and CCT)
The claimed CCT is essentially met – 6000K-6500K claimed and between 6100K and 6800K tested. CRI is low, at around 70.
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 are always with 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
I enjoy multi-emitter flashlights, and I like that the Sofirn SR15 rechargeable flashlight performs (in beam profile) much like a single-emitter light. It also performs (in output) like a quad. Charging works well, and the user interface offers ramping or stepped, too. Very functional!
The Big Table
| Sofirn SR15 rechargeable flashlight | |
|---|---|
| Emitter: | Luminus SFT25R (4) |
| Price in USD at publication time: | $35.24 |
| Cell: | 1×21700 |
| Runtime Graphs | |
| LVP? | |
| Switch Type: | E-Switch |
| Quiescent Current (mA): | ? |
| On-Board Charging? | Yes |
| Charge Port Type: | USB-C |
| Charge Graph | |
| Power off Charge Port | with cell: all modes without cell and/or body: no modes |
| Claimed Lumens (lm) | 4500 |
| Measured Lumens (at 30s) | 2733 (60.7% of claim)^ |
| Candela per Lumen | 22.01 |
| Claimed Throw (m) | 510 |
| Candela (Calculated) in cd (at 30s) | 2200lux @ 5.685m = 71102cd |
| Throw (Calculated) (m) | 533.3 (104.6% of claim)^ |
| Claimed CCT | 6000-6500 |
| Measured CCT Range (K) | 6100-6800 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
- Build quality
- Versatile user interface
- Includes 21700
- USB-C charging works great
- Nice tight beam profile
What I don’t like
- Cool white
- Low CRI
- Quick stepdown on higher modes
Notes
- This content originally appeared at zeroair.org. Please visit there for the best experience!
- For flashlight-related patches, stickers, and gear, head over to PhotonPhreaks.com!
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I have a Sofirn HS40. Great little lamp with a well thought-out user interface. But it has the same problem of stepping down. It means that one can only really use it with the medium brightness setting. Frustrating. I would like a light that will offer at least 1000 lumen over an extended period of time.