The Waterline 1/2" PEX x 3/8" compression angle stop quarter-turn valve controls water flow to household plumbing fixtures. The angle stop valve is used where the water pipe enters the room to allow for easy shut-off of water flow to the end fixture allowing for maintenance and repair without having to turn water off to the entire home. The Waterline 1/2" barb end can be connected to PEX pipe using copper crimp rings or stainless steel clamps. The 3/8" compression outlet with the supplied ferrule and compression nut, can be used with 3/8" pipe or 3/8" supply line. This valve is best suited for use on toilets, faucets, and dishwashers.