Bo stitch BTFP72321 Universal 1/4" Series Coupler - Push-To-Connect - 1/4" NPT Female Thread; features pre-applied thread sealant for airtight connections - this simplifies field installation by eliminating the need for thread sealant tape. Accepts 1/4" series Industrial interchange, 1/4" Automotive interchange or ARO interchange plugs. Designed with corrosion resistant plated steel construction with drag guard for jobsite durability and reliability. The stainless steel 6-ball coupler design is for balanced, strong, secure connections.