The 18650 battery is optimized for use in high-drain devices such as our performance flashlights, and features a Protection Circuit Module (PCM) that guards against overcharging or over-discharging. This battery also features an integrated USB-C charge port. The 18650 includes a Link Case, to safely store, protect, and transport the battery. It features an interlocking design that allows multiple Link Cases to be connected to one another for efficient organization.