ASG 7.2v 500mah battery for Glock, XP17 etc A small 7.2V 500mAh. battery for electric airsoft handguns like: Ref. 15919   G18C, Ref. 16492   CZ99, and Ref. 17508   STI Classic. A NiMH battery offers you a hassle free, reliable and robust power source. They offer a flatter discharge rate, than traditional batteries, Providing a stable rate of fire during their use. Other advantages of NiMH batteries are, that they don’t need to be completely discharged before charging. And they can be rapidly charged in as little as one hour. It is recommended that the battery, be fully discharged once in a while to keep the battery at peak performance.