The Fenix ARB-L16-700UP 16340 lithium-ion battery is specifically designed for high current, high drain devices and makes a great accessory for all current Fenix 16340 (RCR123) powered lights. The benefits of this battery when used in Fenix high drain devices is that they will last longer at their highest performing levels by sustaining a higher voltage. There is also a protection circuit in the anode to help prevent short circuits, over charge/discharge and over-heating. This battery can quickly be charged without the need for a separate charger via its USB port. This not only saves you the expense of purchasing a charger, but also saves the inconvenience of having to carry another device. It is designed to work with: PD25, LD15R, E18R, E16, E15 and HM50R. A micro-USB charging cord is NOT included.