WHK 1/2" inch X 1/2" inch PEX Swivel Fittings are widen also apply RV pex plumbing fittings,such as RV water line fittings,Pex hose fittings,Pex faucet connector,Pex crimp fittingsetc. The pex fittings 1/2 inch has 1/2 NPT Female thread and the Pex end is 1/2 Inch too,The design of 1/2 pex swivel fittings can easy install on RV PEX plumbing Tubing,No need special toolings,Faster and Save your time.The Pex connectors(Pex fittings) has widen compatibility which can fit all kinds 1/2 PEX B or C tubing,such as Everhot, Viega, Zurn, Bow,Watts etc.