Introduction
The Sofirn SP35 is a powerful and versatile LED flashlight designed for various outdoor and indoor activities. It features a Luminus SST-40 LED, offering up to 2200 lumens of brightness, and is powered by a rechargeable 21700 lithium-ion battery. With its Type-C charging port, durable aerospace-grade aluminum alloy body, and advanced temperature regulation, the SP35 provides reliable and efficient illumination.
Package Contents
- Sofirn SP35 Flashlight
- 1x 21700 Rechargeable Lithium-ion Battery (5000mAh)
- USB-C Charging Cable
- 2x Spare O-rings
- Lanyard
- User Manual
Specifications
| Feature | Description |
|---|---|
| Emitter | 1x Luminus SST-40 (50,000 hours lifespan) |
| Operating Voltage | 3.0V – 4.2V |
| Driver | Constant current buck driver |
| Battery Options | 1x 21700 rechargeable lithium-ion battery |
| Dimensions | 126mm (length) × 28mm (head diameter) |
| Weight | 73 grams (without battery) |
| Body Material | Aerospace grade 6061 aluminum alloy, hard-anodized (Type III) |
| Lens | Toughened mineral glass lens |
| Water Resistance | IPX-8 (up to 2 meters underwater, not for diving) |
| Impact Resistance | 1m / 3.28 ft. |
| Charging | USB-C port, input DC 5V 2A |
| Mode Memory | Memorizes last brightness level in general modes (Eco/Low/Med/High) |
| Protection | Reverse polarity, Low voltage warning, Low voltage protection, Advanced Temperature Regulation (ATR) |
| Max Output | 2000 Lumens |
| Max Beam Range | 332 Meters |
| Switch Mode | High/Middle/Low |
| Support Dimmer | 5 - 8 Files |
| Focal Length | Non-adjustable |
Setup
Battery Installation
- Unscrew the tailcap of the flashlight.
- Insert the 21700 rechargeable lithium-ion battery with the positive (+) terminal facing towards the head of the flashlight.
- Screw the tailcap back on tightly to ensure proper contact and water resistance.
Charging
The Sofirn SP35 features a convenient USB-C charging port. To charge the battery:
- Locate the USB-C port on the flashlight body, usually covered by a rubber flap.
- Open the rubber flap.
- Connect the provided USB-C cable to the flashlight's port and the other end to a 5V 2A USB power source (e.g., wall adapter, power bank, computer USB port, car charger).
- The LED indicator on the side switch will show charging status. It typically glows red while charging and turns green when fully charged.
- Once charging is complete, disconnect the cable and securely close the rubber flap to maintain water resistance.
Operating Instructions
The SP35 offers two main mode groups: Stepped and Ramping. You can toggle between them.
Group 1: Stepped Mode (Default)
- Turn ON/OFF: Single click the side switch.
- Cycle Modes: From ON, press and hold the side switch to cycle through Eco → Low → Medium → High. Release the button at your desired brightness.
- Turbo Mode: Double click from OFF or ON.
- Return from Turbo: Single click to return to the previously used mode.
- Moonlight Mode (from Turbo): Double click again from Turbo mode to activate Moonlight.
Group 2: Ramping Mode
Ramping mode allows for stepless brightness adjustment.
- Turn ON/OFF: Single click the side switch.
- Adjust Brightness (Ramp): From ON, press and hold the side switch to steplessly increase or decrease brightness.
- Change Ramping Direction: Release the button and press and hold again within 1.5 seconds to reverse the ramping direction. The light will flash once when it reaches the minimum (Moon) or maximum (Turbo) brightness.
- Turbo Mode: Double click from OFF or ON.
- Return from Turbo: Single click to return to the previously used brightness level.
- Moonlight Mode (from Turbo): Double click again from Turbo mode to activate Moonlight.
Activating Moonlight Mode (from OFF)
- From OFF, press and hold the side switch for 1 second to turn on the flashlight in Moonlight level.
Toggle Between Mode Groups
- From ON, perform 4 fast clicks of the side switch to switch between Group 1 (Stepped) and Group 2 (Ramping).
Strobe Modes
- Activate Strobe: Triple click the side switch from OFF or ON.
- Cycle Strobe Modes: While in Strobe mode, double click again to cycle through SOS → Beacon → Strobe.
Electronic Lockout
The SP35 includes a lockout function to prevent accidental activation.
- Activate Lockout: From OFF, perform 4 fast clicks of the side switch.
- Deactivate Lockout: Perform another 4 fast clicks.
- Moonlight in Lockout: While in lockout mode, press and hold the side switch to temporarily activate Moonlight mode.
Maintenance
- Cleaning: Clean the flashlight body and lens with a soft, damp cloth. Avoid harsh chemicals.
- Lubrication: Apply a thin layer of silicone grease to the O-rings periodically to maintain water resistance.
- Battery Care: Store the battery in a cool, dry place when not in use. Recharge the battery regularly, even if not fully depleted, to prolong its lifespan. Avoid over-discharging or over-charging.
- Threads: Keep the threads clean and lightly lubricated to ensure smooth operation and good electrical contact.
Troubleshooting
- Flashlight not turning on:
- Ensure the battery is inserted correctly with the positive (+) terminal facing the head.
- Check if the tailcap is screwed on tightly.
- Verify the battery is charged.
- Check if the electronic lockout is active (4 fast clicks to deactivate).
- Light steps down automatically or turns off:
- This is likely due to the Advanced Temperature Regulation (ATR) system preventing overheating. Allow the flashlight to cool down.
- The low voltage protection may have activated. Recharge the battery immediately.
- LED indicator flashing rapidly:
- This indicates a low battery voltage warning. Recharge the battery as soon as possible.
- Modes not switching or stuck on minimal brightness:
- Ensure the battery is fully charged. Low voltage can sometimes limit available modes.
- Try resetting the flashlight by unscrewing the tailcap, removing the battery for a few seconds, and then reinserting it.
User Tips
- Color Temperature: Some users prefer the 5000K option for better object distinction, as 6500K can appear too blue and bright without enhancing visibility in certain conditions.
- Cold Weather Performance: The flashlight is designed to operate in cold conditions, but charging lithium batteries in freezing temperatures is not recommended.
- Battery Compatibility: While designed for 21700 batteries, an 18650 battery can be used with an adapter or spacer.
- O-rings: The included rubber O-rings are spare parts for maintaining the flashlight's water resistance. Replace them if the original ones are damaged or worn.
Warranty and Support
For warranty claims, technical support, or any questions regarding your Sofirn SP35 flashlight, please contact the manufacturer or your point of purchase. Keep your purchase receipt as proof of purchase.
