Unprotected, 21700 Li-ion XTAR 35A battery, capacity 3750mAh.

The battery sold does not have electronic protection against overcharging and deep discharging.

Safety precautions:
• use high-quality chargers with charging cutoff at voltage not higher than 4.2V for charging the battery.
• do not allow the battery to discharge below 2.5V
• do not discharge the battery with currents higher than specified below
• do not charge the battery with currents higher than specified below
• do not short-circuit the battery
• do not carry with metal elements (risk of short circuit and burns)
• do not allow the battery to overheat above the temperatures foreseen by the manufacturer
• do not use batteries with damaged casing/foil
• do not use batteries with damaged or dented casing
• do not allow contact with water and other liquids
• do not solder tabs or wires using a regular soldering iron