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Fenix ARB-L21-5000U Li-ion Rechargeable 21700 Battery with Micro USB Charging Port

2 reviews
Save $4.47
Original price $43.32
Current price $38.85



The Fenix ARB-L21-5000U is a high capacity 21700 Li-ion rechargeable battery with a protection circuit in the anode to help prevent short circuits, overcharge/discharge and overheating. The battery also includes pressure relief vents that expel waste gas in the rare case of an internal short circuit preventing an explosion.


USB Type-C charging interface
Button-Top Design
The protective circuit inside the anode
Multiple protection
Over-charge protection
Over-discharge protection
Overheating protection
Short-circuit protection
500 charging circles

Please note that this battery is NOT a 18650 battery and it is not compatible with 18650 battery-powered lights. To use this battery, your device MUST be compatible with 21700 batteries. 

Customer Reviews
5.0 Based on 2 Reviews
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Filter Reviews:
Richard L.
Canada Canada
I bought the Fenix PD36R Flashlight I also bought another spare Battery 5000 mAh, 21700 for a backup for my Flashlight. I was totally impressed with this Flashlight. it is really small and compact and very bright light. I also like the way the 5 settings are and you can lock the setting. I have lot of other Flashlights, but you can not compare the other Flashlights. this Fenix PD36R. Blows the other Flashlights off the list. another thing I love is the USB TYPE-C for charging the Flashlight. I feel I am really set up with extra Battery.

100% I also looked at some other Fenix Flashlights, I wish some of the other Flashlights would not be so high Priced. even the extra Battery 5000 mAh 21700 3.6. 18Wh was quite a High Price to pay. Hope you have a great day.

Dennis M.
Canada Canada