This is a Spektrum RC 1S LiPo 30C 3.7V LiPo Battery with a JST Connector.
Specifications:
Battery Capacity: 300-999mAh
Battery Voltage: 3.7V
Connector Type: JST
Spektrum SPMX8001S30 1S LiPo 30C LiPo Battery (3.7V/800mAh) w/ JST
SKU: SPMX8001S30
$9.99Price