This listing is for a Pack of 1 A washing machine cut-in valve (more commonly called a self-cutting tap or self-piercing valve) is a retrofit water isolation valve designed to create a new water outlet on an existing copper pipe without needing to cut the pipe, solder joints, or drain down the water system. Inline shut-off valve designed to supply clean water to a washing machine or dishwasher while providing quick, local isolation for servicing or emergencies. Clamps around an existing copper pipe and drives an internal hollow cutter through the pipe wall to tap into the water supply without needing to cut or drain the line. Connects washing machines and dishwashers to water supply