Male Pipe Schrader Twist-Lock Coupler SKU Body Size Threads Length HFTL-251-04MP 1/4 1/4-18 NPT 2.22 HFTL-251-06MP 1/4 3/8-18 NPT 2.28 HFTL-501-06MP 1/2 3/8-18 NPT 2.55 HFTL-501-08MP 1/2 1/2-14 NPT 2.61