Watts 3001A Dielectric Unions are used in commercial and residential applications to prevent accelerated corrosion and deterioration in the piping system due to galvanic and stray current. It is installed between pipes made from dissimilar metals, and features a female iron pipe thread to solder connection. It consists of a union nut, two tailpieces, and a gasket that separates the tailpieces to prevent an electric current from occurring. Series 3001A is ideal in applications such as hot water storage tanks, water and air conditioners, processing tanks, steam, gas, and water piping. Maximum Pressure: 250psi.