Spring down variable rate air control kit w/small air tank (set) this is a complete air-control kit for use with any pneumatic-operated retracts air up & spring down. The kit includes: small air tank, 6 ft. Orange air line, fittings, one way variable rate control valve, fill valve, and fill fitting. The operating valve requires approximate 1/4"" of push rod travel and functions with standard or mini servos. (servo & push rod not included) max operating pressure 110 psi. (rob-184vr)