This is the EcoPower 5-Cell NiMH AA SBS-Flat Receiver Battery with a Receiver Connector. This battery features 2000mAh capacity is ideal for use as a rechargeable battery for your transmitter, as well as many other applications. The recommended charge rate for these batteries is 1C for the best battery life and run time. Specifications: Chemistry: NiMH Voltage: 6.0 nominal Number of Cells: 5 Capacity: 2000mAh Weight: 136g Dimensions: 53x72x15mm Connector Type: Rx Configuration: SBS-Flat Max Charge Rate: 1C (ECP-5010)