The flashlight was sent to me by Sofirn for review.
Here’s the product’s link: Sofirn SP31 V3 (non-affiliate)
The Sofirn SP31 V3 comes in a normal cardboard box.
The following accessories are included with the flashlight bundle:
- Sofirn-branded 18650 cell
- USB Type-C charging cable
- 2 x replacement o-rings
- Lanyard
The flashlight comes with black, matte anodization and heavy texturing around its whole body.
The light is operated by dual switches.
The mode selection is operated via the e-switch that’s mounted on its head.
While, the on/off operation is dictated by the rear, mechanical switch.
The rear switch sits slightly below the two metal flaps, which in turn allows the flashlight to tailstand.
The protruding flaps also contain a couple of holes to allow for the installation of a lanyard.
The e-switch is illuminated and will light up during turn-on or charging to indicate the battery’s state.
Opposite to the e-switch, we find the charging interface of the flashlight.
A rubber flap is used to keep moisture and dust away.
A regular USB Type-C port is used on the charging interface of the flashlight.
Looking at the front of the head, we see a TIR lens that’s sits under the subtly protruding bezel.
The Sofirn SP31 V3 comes with a Luminus SST40 emitter.
The head can be easily disassembled.
Here’s the MCPCB of the light. As we can se it’s held into place with a couple of screws and plenty of thermal paste is in used.
The back side of the head is where the driver of the light is located.
The driver seems to be press fit into place and a short copper spring is used as the positive terminal.
The body and tail pieces of the light are glued together.
The head-side threads of the light come anodized with a square cut and plenty of lubrication in place.
A dettachable pocket clip also comes with the light.
The clip provides strong retention.
The weaving pattern on its end helps with lifting it while mounting the flashlight on your pocket.
Finally, the bundle also includes a Sofirn-branded 18650 cell w/ 3000mAh of rated capacity.
The cell is button top.
User Interface
The dual switch design of the flashlight creates a very simple user interface.
Here’s all the supported actions:
Turn on/off: Single press of rear switch.
Mode Cycle: Single press of e-switch ( Low > Medium > High > Turbo > Low > …)
Moonlight: Turn on while pressing the e-switch.
Strobe: Long press of the e-switch while turned on.
SOS: Single press of e-switch while on Strobe.
The flashlight’s driver includes Low Voltage Warning via the indicator LED and Low Voltage Protection. The flashlight will turn off if the battery’s voltage goes below 2.8V
Output
Here’s my output measuremnets for different modes of the flashlight along with their current draw.
As we can see, the flashlight is able to push almost 1900 OTF lumen at turn on.
Mode space looks pretty good and the existence of Moonlight is highly appreciated.
Power Regulation
Here’s a graph demonstrating the flashlight’s power regulation capabilities.
The graph was generated using my bench power supply.
What we can see in the graph:
- Overall the flashlight shows very good signs of power regulation.
- Turbo is fully regulated down to 3.7V
- High is fully regulated down to 3.1 V
- The rest of the modes are fully regulated.
- Turbo and High will drop to Medium at 3.1V
- (Not visualised) Cut-off happens at 2.8V