Tap the tactical switch to momentarily turn on the light, release it and the light will go out. Fully press the tactical switch to constantly turn on the light, fully press again to turn off the flashlight.
White Light mode: With the white light switched on, single click the functional switch to cycle through Low→Med→High→Turbo.
Red/Green light mode: With the red/green light switched on, single click the functional switch to cycle through Low→High.
With the light switched on, press and hold the functional switch to cycle through White Light mode→Red Light mode→Green Light mode.
With the light switched off, press the functional switch to enter Strobe, release it and the light will go out.
Intelligent Memory Circuit
The light memorizes the last selected output, excluding strobe. When turned on again, the previously used output will be recalled.
Fenix ARB- L21-5000 V2.0
Fenix ARB- L21-5000U
Fenix ARB- L21-4000P
Other types of Li-ion battery
*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; cell damage or short circuiting are considered user induced damage and are not covered by any Fenix warranty or liability.
Unscrew the tail cap and insert the battery with the anode side (+) towards the light head, then screw the tail cap back on.
Intelligent Overheat Protection
The light will accumulate a lot of heat when used at high output levels for extended periods. When the light reaches a temperature of 65°C/149°F or above, the light will automatically step down a few lumens to reduce the temperature. When the temperature drops below 65°C/149°F, it will then gradually return to the standard output level.
When the voltage level drops below the preset level, the flashlight is programmed to downshift to a lower brightness level until Low output is reached. When this brightness level is reached (Low output), the light blinks 3 times every 5 minutes to remind users to recharge or replace the battery.
Note: This feature only works with a Fenix ARB-L21 series rechargeable battery.
Usage and Maintenance
- Disassembling the sealed head can cause damage to the light and will void the warranty.
- 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.
- Remove 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.
- DO NOT place this flashlight in the reach of children!
- Do NOT shine the flashlight directly into the eyes of anyone!
- Do NOT place light head near flammable objects, high temperatures can cause objects to overheat and become flammable/ignite!
- Do NOT use the flashlight in inappropriate ways such as holding the unit in your mouth, doing so could cause serious personal injury or death if the flashlight or internal battery fails!
- This flashlight will accumulate a significant amount of heat while operating, resulting in a high temperature of the flashlight shell. Pay close attention to avoid burns.
- 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 will need to be replaced when the LED reaches the end of its lifespan.