CPS Products Pro-Set air conditioner gauge set features rugged diaphragm valves and easy one full turn open and close valves. The black anodized aluminum block body is designed with an oversized optical sightglass for better viewing of refrigerant being added. This gauge set includes 1/4" chrome R134a field services couplers and a 1/4"-1/2" ACME vacuum pump adapter. The Premium 72" hoses are designed to accept all refrigerant types.