BTG 3.7V 780mAh Rechargeable Li-po Battery (4pcs) + 4in1 X4 JST Charger for JJRC H51 Drone Wltoys V636 V686 V686G V686K Quadcopter Spare Parts FOR SAFETY PURPOSE, PLEASE READ "CAUTION" OF THE BATTERY BEFORE USE!!! Upgrade: 3.7V 780mAh Rechargeable Li-po Battery with JST plug 4in1 JST Charger: Can charge 4 batteries at one time Compatible with JJRC H51 Drone and Wltoys V636 V686 V686G V686K Quadcopter Package inclduing: 4x batteries; 1x 4in1 JST charger