On/off

Rotate the mechanical side switch in clockwise to turn on the light; rotate the mechanical side switch to OFF to turn off the light.

Output Selection 

Rotate the mechanical side switch to cycle through OFF⇄Low⇄Med⇄High⇄Turbo⇄SOS⇄Strobe.

Strobe

Rotate the mechanical side switch to the rightmost position to select strobe output.

Battery Specifications

Warning: Do not mix batteries of different brands, sizes, capacities or types. Doing so may cause damage to the flashlight or to the batteries being used.

*21700 Li-ion batteries are powerful cells designed for commercial applications and must be treated with caution and handled with care. Only using quality batteries with circuit protection will reduce the potential for combustion or explosion; but cell damage or short circuiting are considered user induced damage and are not covered by any Fenix warranty or liability.

Battery Replacement

Unscrew the light body and insert the battery with the anode side (+) towards the light head, then screw the light body back on.

Charging 

1. First switch off the light and plug the USB A socket of the charging cable into an appropriate A/C powered USB plug/outlet, then connect the USB Type-C socket of the charging cable to the light. 
2. The indicator will display red while charging, and will turn to green when fully charged. 
3. Once charging is completed, be sure to unplug the charging cable and close the anti-dust cover. 
4. Only low and med outputs are available while charging.

Note:

1. The normal charging time of the included Fenix ARB-L21-5000 V2.0 rechargeable battery is approximately 3 hours from depleted to fully charged.
2. Recharge a stored light every four months to maintain optimum performance of the battery.

Battery level indication 

When the light is switched on, the battery level indicator besides the charging port will light up to display the battery status, the indicator will stay on for 3 seconds before it goes off. 

Green light on: saturated 100% - 85%

Green light flashes: sufficient 85% - 50%

Red light on: poor 50% - 25%

Red light flashes: critical 25% - 1%

Note: This feature only works with the Fenix ARB-L21-5000 V2.0 battery and the Fenix ARB-L21-4000P battery.

Intelligent Overheat Protection            

The lamp will accumulate a lot of heat when used at relatively high output levels for extended periods. When the lamp reaches a temperature of 60°C or above, the lamp will automatically step down a few lumens to reduce the temperature. When the temperature drops below 60°C, it will then allow the user to select these modes again. 

Low-voltage Warning

When the voltage level drops below the preset level, the lamp is programmed to downshift to a lower brightness level until Low output is reached. When this brightness level is reached (Low output), the battery level indicator blinks to remind you to recharge or replace the battery. 

Note: This feature only works with the Fenix ARB-L21-5000 V2.0 battery and the Fenix ARB-L21-4000P battery.

Usage and Maintenance 

• Disassembling the sealed head can cause damage to the light and will void the warranty.
• Fully charge the light in time to ensure normal use next time. 
• Fenix recommends using an excellent quality battery. 
• If the light will not be used for an extended period, remove the battery, or the light could be damaged by electrolyte leakage or battery explosion.
• Unscrew the tail cap half a turn or take out the battery to prevent accidental activation during storage or transportation.
• Long-term use can result in O-ring wear. To maintain a proper water seal, replace the ring with an approved spare．
• Periodic cleaning of the battery contacts improves the lamp's performance as dirty contacts may cause the lamp to flicker, shine intermittently or even fail to illuminate for the following reasons:
  A: Poor battery level.
  Solution: Replace or recharge the battery (Ensure the battery is inserted according to the manufacturer’s specifications).
  B: The threads, PCB board contact or other contacts are dirty. 
  Solution: Clean the contact points with a cotton swab soaked in rubbing alcohol.

If the above methods don't work, please contact your authorized distributor.

Warning

• Do NOT shine the flashlight directly into the eyes of anyone!
• If any of the information provided in this manual is changed, the new version of the manual shall prevail; if your included user manual is an old one, it is the responsibility of the customer to acquire an updated one.
• DO place this flashlight in the reach of children!
• Do NOT shine flammable objects at close range, to avoid burning objects or causing danger due to high temperature!
• Do NOT use the flashlight in inappropriate ways such as biting in the mouth, to avoid personal injury or life threats when the flashlight or internal battery fails!
• This flashlight will accumulate a lot of heat while operating, resulting in a high temperature of the flashlight shell. Pay close attention to safe use to avoid burns.
• Turn off and lock the flashlight or remove the battery from the flashlight to prevent accidental activation when the flashlight is placed in a closed-in and flammable environment such as pockets and backpacks!
• The LED of this flashlight is not replaceable; so the whole flashlight should be replaced when the LED reaches the end of its lifespan.