Batteries and chargers from Fenix deliver consistent output across sizes, with rechargeables and chargers built for the task. Matched to the standards of Fenix flashlights, headlamps and bike lights, these products combine safe operation with reliability even in adverse conditions. The Fenix ARB-L18-3500 is a high capacity 18650 Li-ion rechargeable with a protection circuit in the anode to help prevent short circuits, over charge/discharge and over heating. The battery also includes pressure relief vents which expel waste gas in the rare case of an internal short circuit preventing an explosion. With outstanding performance, excellent reliability and compact design, it is the best match for your high-drain devices.Features3500mAh high capacity battery with outstanding performanceProtection circuitry to prevent short circuitsPressure vents to prevent explosions500 charge cyclesCharging Current: Recommended 1A, maximum 2A