The Ball Check valves prevent back flow or drain down in the system. The true union provides easy access for inline installation and servicing. The true union ball check is designed for quick positive sealing with minimum turbulence, low restriction, and efficient fluid transfer. It can be installed vertically or horizontally. System pressure will unseat the ball, allowing flow. Back flow or head pressure of 30” or 1 to 2 psi will seat the ball and stop back flow. Each check valve ships with female thread and socket adapters. This valve is manufactured 100% from thermoelastic materials, making is less susceptable to corrosion.