Put the power in clear lighting. Compatible exclusively with the COAST PX250 and SX300R PURE BEAMA(R) flashlight, the ZX400 ZITHION-X(TM) rechargeable lithium polymer battery pack has a built-in USB port and recharges inside or outside the light-creating a no-hassle, lightweight power solution. Overcharge/discharge protection circuits make powering up as simple and safe as possible. The battery pack is backed by COAST's one-year warranty against defects in materials and workmanship. All COAST ZITHION-X(TM) batteries are protected with premium overcharge/discharge protection and are backed by COAST's one-year warranty.