McAlpine SA10V Anti-Syphon Swivel P-Trap

This white plastic 32mm (1.1/4") anti-syphon P-trap is a standard fitting suitable for installation underneath a basin to enable the removal and redistribution of waste water. Whenever syphonic conditions develop, the negative pressure causes the anti-syphonic valve to rise ...This white plastic 32mm (1.1/4") anti-syphon P-trap is a standard fitting suitable for installation underneath a basin to enable the removal and redistribution of waste water. Whenever syphonic conditions develop, the negative pressure causes the anti-syphonic valve to rise, allowing air to be drawn into the discharge pipe.

The pressure is thereby neutralised before it can have any effect on the water seal within the Trap. On cessation of the syphonic action, the Valve closes, making the anti-syphon trap air and watertight.