The flashlight was sent to me by Sofirn for review.
Here's the product's details: Sofirn SP33S
The flashlight comes in a regular cardboard box.
The following contents are included in the package:
- Sofirn 26650 battery w/ 5000mAh of capacity.
- USB-C charging cable.
- Lanyard.
- 2 x replacement o-rings.
- User manual.
The SP33S comes in matte black anodisation and has a subtle design.
It's opertaed via an e-switch that's mounted in the lower part of the head.
The e-switch is slightly protruding and provides a tactile feedback.
An LED is embedded into the switch and is used to indicate the battery's level during normal operation or charging.
It's also worth noting that the switch can be programmed to stay on while the flashlight is turned off.
The charging port is mounted opposite to the switch.
A rubber flap is in place to keep moisture and dust out of the charging interface.
The charging takes place using a regular USB-C cable.
A few thick heathsinking grooves are incorporated into the head's design.
The body of the flashlight comes with some nice horizontal grooves that improve the overall grip.
The front part of the head makes use of a metal polished bezel that helps protect the glass lens.
Looking into the head, we can see a light orange-peel reflector along with a nicely centered Cree XHP70.2 emitter.
The driver seems to be press fit and glued in place.
A brass tab is used as the positive terminal.
The tail implements an anti-roll pattern and also includes a hole for attaching the lanyard.
The tail houses a thick copper spring.
Both the front and rear threads are very cleanly cut and arrived anodized, which allows the flashlight get mechanically locked out.
The tail is completely flat which allows the flashlight to tailstand.
User Interface
The following actions are supported by the flashlight's firmware:
Turn on/off: Single press.
Ramp Up/Down (when in ramping mode): Long press while on. Releasing and pressing the switch again will change the ramping direction.
Mode cycle (when in stepped mode): Long press (Low > Mid > High).
Turbo: Double press.
Moonlight: Long press from off.
Strobe: Triple press
Lockout: Quarduple press while off.
Switch from ramping to stepped modes: Quadruple press while on.
Configure Indicator LED: 5 x clicks while off ( ON > Blinking > OFF)
Mode memory is on.
Low Voltage Warning and Low Voltage Protection is present.
Output
Here's my output measurements along with the respective current draw (stepped mode).
As we can see, the Sofirn SP33S is able to push more than 4600 lumen OTF at turn on.
The moonlight is also quite good at 9lm, provided that we're talking about an XHP70.2 flashlight.
Power Regulation
Here's a power regulation graph of the stepped output modes of the Sofirn SP33S.
What we can see in the graph:
- Turbo's power regulation seems very interesting. It seems to follow some kind of 'stepped' regulation for Turbo.
- The full output of Turbo is sustained up until the 3.8V level.
- High is fully regulated up until 3.3v.
- Medium and Low are fully regulated for the whole span of the battery's voltage.
Thermal Regulation
Here's a Thermal Regulation graph I've created for Turbo and High.
The graph was recorded while using a high drain 21700 cell.
What we can see in the graph:
- Turbo's full output is sustained for 1 minute and 20 secs. Post the 1:20 mark, the output is regulated to keep the flashlight's thermals in place.
- High's full output is sustained for 21 minutes. Thermal regulation kicks in after that.
- Both modes show signs of true thermal regulation - The output will constantly increase/decrease in order keep the flashlight's max temp constant.
- The thermal regulation uses a ramping pattern to adjust the brightness. No sharp / sudden changes can be observed.