Lectron Pro 7.4V 4000mAh Lipo TX Battery for the Spektrum DX7S, DX8, and DX9 Transmitters Lectron Pro batteries feature a high-end performance and reliability at an affordable price! Battery Voltage: 7.4V | Capacity: 4000mAh | Maximum Continuous Discharge Rate: 5C (20 Amps) | Maximum Charge Rate: 2C (8 Amps) Battery Dimensions: 68mm x 52mm x 19mm / 2.7in x 2.1in x 0.8in | Weight: 143g Works great with Spektrum DX7S, DX8, and DX9 Transmitters (Always check the voltage, dimensions, and battery connector to ensure this battery will be a good fit for your vehicle/application) We're confident in quality of our batteries! All Lectron Pro batteries are covered by a 1 Year Warranty against any manufacturing defects and U.S. based support in case you run into any issues!