The Mongoose J3 is a Toy system that requires a 12V 15Ah AGM replacement battery. The compatible Universal Power Group replacement is the UPG UB12150 12V 15AH F2 AGM Battery (UB12150), a 12V 15Ah AGM sealed lead-acid battery. This battery delivers up to 180 watts of standby power. It weighs 8.5 lb, uses F2 terminals, measures 6 L x 3.8 H in, and has left polarity. This is a direct drop-in replacement for the Mongoose J3 requiring no modification to the device.
