High Capacity, High Power Nickel Metal Hydride Battery Pack, NiMH technology enables convenient charging at any time. There's no cell memory effect and no need to fully discharge before recharging. High power delivery with 38 Amp maximum discharge rate. Compatible and designed specifically for high performance with iRobot Looj Gutter Cleaning Robot. Also manufactured for high RC Racing performance. Fits popular standard 7.2V RC cars, such as Traxxas, LOSI, Associated, HPI, Tamiya, Kyosho, etc. 6 months manufacturer warranty. Standard Charge: 12 hours @ 300mA. Rapid Charge: 1.5 hours @ 3000mA