Noiposi 5pcs 3.7v 850mah 25c Upgrade Rechargeable Lipo Battery with X6 Charger Compatible with X5SW X5SC X5SC-1 X5SW-1 CX-30W RC Quadcopter (850mAh) High Capacity Battery:3.7v 850mAh will bring you more power and longer flying time Multifunctional Chagrer :the charger is with Over charge protection and Short circuit protection.while the voltage of battery is close to 4.2v ,the charger will stop .it will protect batteries from the damage .Thus ,the lifetime of batteries will be longer Connector type:Losi Compatible With : X5SC X5SW CX-30W RC Quadcopter Well-designed appearance and new package :if you want to buy a gift for your relative ,friend or yourself ,it is a good choice