SharkBite PEX Barb threaded male adapter is made of a lead-free DZR brass, and is an easy-to-install, low-cost solution to connect to PEX tubing. These fittings allow you to connect with either a stainless steel clamp system, or a copper crimp ring system (each sold separately) and is FNPT threaded on the other side. The SharkBite PEX Barb fittings are compatible for potable water distribution and hydronic heating applications. Approvals: ASTM F1807, NSF/ANSI 61, NSF 372.