This motor casing allows a wide range of propellant types and motor classifications to be used for mid power rocketry. The case is reuseable for an unlimited number of flights. Just unscrew the forward and rear closures, remove the spent propellant kit, clean and grease the casing and reload. The directions do need to be followed closely, if a part is put in the wrong place it could cause the motor to CATO. The casing pays for itself in 3-4 flights when you compare the cost of single use motors to the reload kits that are available.