Each Rapid Blaster comes equipped with a rechargeable battery that controls the fully automatic firing system which gives you up to 4-5 hours of continuous playing time. The battery can be recharged with the USB charging cable which comes included. Gel Balls can be grown to full size (7mm-8mm) in 3-4 hours after being hydrated in water. Always make sure that the Gel Balls are grown to full size before using them in the Rapid Blasters. If the Gel Balls are not grown to full size this may cause the Rapid Blaster to not properly function. It's recommended to let the balls soak in a 1 gallon bucket of water while hydrating a 5,000 round packet.