Install TipsThe 1 inch union check valve Must be installed for Vertical direction, and must be installed correctly following with swing check valve's main body arrow mark direction, Otherwise the 1 inch true union check valve will not work well.True Union Ball Check ValveThe 1 inch union check valve is disigned with a ''Ball'' inside which is used for preventing backflow (only allow flow for one direction). (No Spring Inside)Excellent SealingThe inside ball and the washers provide 1 inch pvc swing check valve with an excellent sealing when the fluid flows back. Easy to Install DemolishYou can install or demolish the 1 inch union swing check valve easily due to the slip swing full port design, even remove for cleaning without breaking down the piping connection.Widely CompatibleThe 1 inch pvc check valve can be used in a variety of applications however they are commonally used for irrigation, pool building or home plumbing systems for preventing backflow, ensuring the proper operation of the system and preventing damage from happening.Premium MaterialThe 1 inch union check valve's main body is made of PVC high quality material and the O-ring is made of EPDM material. Premium material make the pvc union check valve durable, strong.PVC Union Check ValveThe union swing check valve kit comes with 1pcs 1'' true union check valve with slip swing full port, 2pcs washers of different widths for your extral need.