The Fenix WF25RM is a multifunctional cradle-charging duty light with 3000 lumens max output, 370 meters max beam distance, and a built-in 365nm UV light mode for inspection and leak-testing work. This summary is drawn from the manufacturer's official user manual — see the downloadable PDF reference manual on the product page for complete details.
Key Features
- 3000 lumens maximum output, 370 meters maximum beam distance.
- Utilizes one Luminus SST70 LED with a lifespan of 50,000 hours.
- Includes a Fenix ARB-L21-5000U rechargeable battery.
- Magnetic charging cradle that can be separated from the magnetic charging cable; the cradle can also be fixed to a desk or wall with two screws.
- Neck-mounted switch supports a long press to instantly enter Burst output.
- 365nm UV light mode for non-destructive testing and leak detection.
- Proximity downshift safety function to prevent overheating when the light head is close to an illuminated surface.
- Boot-up battery level indication and low-voltage warning.
- Made of durable A6061-T6 aluminum alloy with a premium HAIII hard-anodized anti-abrasive finish.
- Flashlight size: 7.17" x 1.57" x 1.57" / 182 x 40 x 40 mm.
- Charging cradle size: 3.02" x 1.72" x 1.85" / 76.7 x 43.7 x 47 mm.
- Weight: 8.80 oz / 249.5 g (including battery).
Technical Parameters (ANSI/PLATO FL1) — White Light
- Burst: 3000 lumens, 1 hour 50 minutes*, 370 m (1,214 ft), 34,225 cd
- High: 1000 lumens, 3 hours 10 minutes, 210 m (689 ft), 11,025 cd
- Med: 400 lumens, 7 hours 30 minutes, 130 m (427 ft), 4,225 cd
- Low: 150 lumens, 22 hours 20 minutes, 80 m (262 ft), 1,600 cd
- Eco: 30 lumens, 77 hours, 30 m (98 ft), 225 cd
UV Light: 500mW output (365nm). Impact resistance: 1 meter. Submersible: IP68. *Burst runtime is measured in total, including reduced output resulting from the light's temperature-protection mechanism. Tested per the ANSI/PLATO FL1 standard using one Fenix ARB-L21-5000U battery at 21±3°C / 50–80% humidity; real-world performance may vary depending on the working environment and battery used.
Operating Instructions
White Light On/Off: With the light turned off, press and hold the switch for 0.5 seconds to turn on the White light. Single click the switch to cycle through Eco → Low → Med → High. Press and hold the switch for 0.5 seconds again to turn off the White light.
UV Light On/Off: With the light turned off, double click the switch within 0.5 seconds to turn on the UV light. Press and hold the switch for 0.5 seconds again to turn off the UV light.
Burst: In any state, press and hold the switch for 1.2 seconds to enter Burst; release it and the light will return to its previous status.
Intelligent Memory Circuit: The flashlight automatically memorizes the last selected output, excluding Burst. When turned on again, the previously used output will be recalled.
UV Light Indication
Because UV light is invisible, the indicator will continuously and alternately blink red and green to indicate that UV light output is selected. When the UV light output is selected and the voltage level drops below the preset level, the indicator will blink red to prioritize the low-voltage warning.
Proximity Downshift Safety Function
When the light head is close to an illuminated object (<1 cm), the flashlight will automatically downshift the brightness level to Eco output to avoid burns caused by high temperature. This function only applies to the Burst output and High output. Unscrew the tail cap, then long press the switch while screwing the tail cap back on; the light will blink white three times, indicating that this function is temporarily disabled. Re-inserting a battery will re-enable this function.
Battery Specifications
- Fenix ARB-L21-5000 V2.0: 21700, 3.6V — Recommended
- Fenix ARB-L21-4000P: 21700, 3.6V — Recommended
- Fenix ARB-L21-5000U (included): 21700, 3.6V — Recommended
It is strictly prohibited to use an 18650, a CR123A, or a 16340 battery. 21700 Li-ion batteries are powerful cells designed for commercial applications and must be treated with caution and handled with care. Using low-quality batteries or mishandling batteries (such as short-circuiting or overheating) could lead to combustion and jeopardize the safety of users and property. Any adverse effects resulting from the use of low-quality batteries are not covered by any Fenix warranty or liability. Using quality batteries with circuit protection will reduce the potential for combustion or explosion.
Battery Replacement
Unscrew the light tail to insert the battery with the anode side (+) towards the light head, then screw the light tail back on.
Charging (Magnetic Charging Cradle)
- Plug the USB-A end of the magnetic charging cable into an electrical outlet or USB power source, then connect the charging port of the flashlight to the magnetic charging port in the cradle.
- The indicator will display red while charging and will turn green when fully charged.
- The magnetic charging cradle can be separated from the magnetic charging cable, and the cable can also be used on its own without the cradle.
- The magnetic charging cradle can be fixed to a desk or wall using two screws for a stationary charging station.
- The normal charging time of the included Fenix ARB-L21-5000U battery is approximately 2 hours 45 minutes from depleted to fully charged when the charging input is 5V/3A or above.
Note: Recharge a stored light every four months to maintain optimum performance of the battery.
Battery Level Indication
With the light turned off, single click the switch to check the current battery level; the indicator will last for 3 seconds. Each time the light is turned on, the indicator will also show the current battery level for 3 seconds.
- Green light on: saturated, 100% - 85%
- Green light flashes: sufficient, 85% - 50%
- Red light on: poor, 50% - 25%
- Red light flashes: critical, 25% - 1%
*This feature only works with a Fenix ARB-L21 Series 21700 rechargeable battery.
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 60°C/140°F or above, it will automatically step down a few lumens to reduce the temperature. When the temperature drops below 60°C/140°F, the light will gradually recall the preset output level.
Low-Voltage Warning
When the voltage level drops below the preset level, the light is programmed to downshift to a lower brightness level until Eco output is reached. When this happens in Eco output, the indicator blinks red to remind users to recharge or replace the 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.
- 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 light's performance, as dirty contacts may cause the light to flicker, shine intermittently, or even fail to illuminate. If this happens: A. Poor battery level — replace or recharge the battery. B. The threads, PCB board contact, or other contacts are dirty — clean the contact points with a cotton swab soaked in rubbing alcohol. If the above methods don't work, please contact your authorized distributor.
Warnings
- Do NOT place this light in the reach of children.
- Do NOT shine the light directly into the eyes of anyone.
- Do NOT place the light head near flammable objects; high temperatures can cause objects to overheat and become flammable/ignite.
- Do NOT use the light in inappropriate ways such as holding the unit in your mouth, doing so could cause serious personal injury or death if the light or internal battery fails.
- This light will accumulate a significant amount of heat while operating, resulting in a high temperature of the light shell. Pay close attention to avoid burns.
- Take out the battery to prevent accidental activation during storage or transportation.
- The LED of this light is not replaceable; the light will need to be replaced when the LED reaches the end of its lifespan.
What's Included
- Fenix WF25RM flashlight
- ARB-L21-5000U battery
- Charging cradle
- Magnetic charging cable
- Spare O-ring
- User manual
- Warranty card
