The SharkBite PEX Poly Alloy Barb Connector is an easy to install, low-cost solution to connect to PEX tubing to an NPT threaded pipe or fitting. They are suitable for potable water distribution and hydronic heating applications. SharkBite PEX Poly Alloy Barb fittings can be used in both a stainless steel clamp system, or a copper crimp ring system as well (each sold separately). Approvals: ASTM F2159, NSF/ANSI 61, NSF 372.