Sofirn SR23 Rechargeable Flashlight Review
The Sofirn SR23 Rechargeable flashlight features three TN-3535 warmer-than-6000K emitters and a UV right beside them. USB-C charging, too! Read on for testing!
Official Specs and Features
Here’s a link to the Sofirn SR23 Rechargeable flashlight product page.
Versions
Looks like there’s just one version of the Sofirn SR23 Rechargeable flashlight.
Price
The Sofirn SR23 Rechargeable flashlight lists for somewhere in the $60 range, but is available right now around $41.
What’s Included
- Sofirn SR23 Rechargeable flashlight
- Sofirn 5000mAh 21700
- Charging cable
- Lanyard
- Spare o-rings (2)
- Manual
Package and Manual
Build Quality and Disassembly
The Sofirn SR23 Rechargeable flashlight has an interesting design feature that Sofirn hasn’t used much (but maybe has used at least once before). There’s a silicone grip area along the cell tube here!
The build quality is good. Both the head and tail have nice thick springs.
The cell tube has anodized threads and on both ends.
Size and Comps
Size: 31.5 mm x 114.9 mm
Weight: 86g(without battery)
If the flashlight can headstand, I’ll show it here. If it can tailstand, I’ll also show that here!
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
A two-way friction-fit pocket clip is included.
A lanyard is also included. It could attach to the pocket clip, but there’s a loop in the tailcap too.
The tailcap magnet is strong enough to hold the Sofirn SR23 Rechargeable flashlight securely.
Power and Runtime
The Sofirn SR23 Rechargeable flashlight is powered by one lithium-ion cell. Sofirn includes this standard flat-top 5000mAh 21700.
The cell goes into the Sofirn SR23 Rechargeable flashlight in the usual way – positive end toward the head. It’s not shown here, but the tailcap has a little logo to indicate the cell direction, too.
The Sofirn SR23 Rechargeable flashlight offers only ramping, so I tested turbo twice and just a couple of other random modes. Turbo steps down quickly, but interestingly, there’s some variation in how it steps down. In one test, it held steady for around a minute. In another, it dips nearly immediately, then holds steady for around 1.5 minutes.
After the light steps down to around 900 lumens, output is very steady for nearly 2.5 hours.
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. Temperature sensors are attached however feasible and not always on the bezel or hottest spot (assuming that can even be clearly defined). Even with ideal placement, too many variables affect temperature to definitively state a specific max value.
Charging
The Sofirn SR23 Rechargeable flashlight offers USB-C charging. The charge port is in the head.
A USB-C to USB-C charging cable is included.
Charging looks fine and is consistent with C or A input. Charging takes just over 3 hours.
While charging, the indicator 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 | 3300-1100 | 90s-150m | 2808 (0s) 2752 (30s) |
8.45 |
| Lowest | 5 | 290h | 5 | [low] |
| UV High | – | 4.5h | – | 0.66 |
| UV Low | – | 23h | – | 0.15 |
Pulse Width Modulation
Neither of the steady modes uses 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 SR23 Rechargeable flashlight has two e-switches. They both have an indicating feature, which can be seen below.
When you turn the Sofirn SR23 Rechargeable flashlight on, the switch indicates the approximate cell voltage for around 5 seconds, as follows:
Green solid: 75-100%
Green flashing: 50-75%
Red solid: 25-50%
Red flashing: 1-25%
Here’s a user interface table!
| State | Action | Result |
|---|---|---|
| Off | Click UV switch | UV on (memory) |
| UV on | Hold UV switch | Iterate Low/High UV |
| UV on | Click UV switch | Off |
| Off | Click LED switch | LED on (memory) |
| LED on | Hold LED switch | Stepless LED output increase (to either endpoint) |
| LED on | Release hold, then hold again | Change ramp direction |
| Any | Click LED switch 2x | LED Turbo |
| Turbo | Click LED switch 2x | Iterate between Low and Turbo |
| Any | Click LED switch 3x | Strobe |
| Strobe | Click LED switch 3x | Iterate between SOS and Strobe |
| Off | Hold LED switch | Low |
| Off | Click LED switch 4x | Iterate Lockout |
LED and Beam
Three of the emitters seen below are TN-3535 emitters, at a claimed 6500K-7000K. The other is UV.
The three white LEDs operate in unison; there is no mode where they operate individually.
LED Color Report (CRI and CCT)
The claim here is “6500-7000K” but I measured well below that, peaking at under 6000K for the highest mode. That’s good (for me, and probably for you). The Duv is positive, which means you might pick up some green in the output. 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
At $40, the Sofirn SR23 Rechargeable flashlight is a good way to get high output and UV. It’s particularly good if you’re looking for a 900-lumen flashlight, because once any mode steps down, the light holds 900 lumens very steadily. That’s great! I appreciate UV having a dedicated switch, and otherwise not really getting in the way of white LED output. USB-C charging looks great, and I’m glad that this light uses a standard cell, too!
The Big Table
| Sofirn SR23 Rechargeable flashlight | |
|---|---|
| Emitter: | TN-3535 (3) + UV |
| Price in USD at publication time: | $40.99 |
| Cell: | 1×21700 |
| Runtime Graphs | |
| LVP? | Yes |
| 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 tailcap: no modes |
| Claimed Lumens (lm) | 3300 |
| Measured Lumens (at 30s) | 2752 (83.4% of claim)^ |
| Candela per Lumen | 3.8 |
| Claimed Throw (m) | 200 |
| Candela (Calculated) in cd (at 30s) | 275lux @ 5.795m = 9235cd |
| Throw (Calculated) (m) | 192.2 (96.1% of claim)^ |
| Claimed CCT | 6500-7000 |
| Measured CCT Range (K) | 5700-5900 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
- Reasonable cost
- Separate switch for UV
- Good charging
- Warmer output than claimed
What I don’t like
- The grippy side bit
Notes
- This content originally appeared at zeroair.org. Please visit there for the best experience!
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