Milton (S-659) 1/4" NPT Full-Swivel Air Hose End Fitting (Female)1/4" FNPT swivel hose ends help eliminate kinked and twisted airlines. Offers a full 360-degree swivel and made of steel construction with a black oxide finish. This is the ?" NPT female hose end. For the ?" NPT male hose end (Barb ?" ID): Milton #658For the ?" NPT male hose end (Barb ?" ID): Milton #658-1