Polypipe 40mm Washing Machine Trap 75mm Seal with Upstand Pipe and 2 Clips White is used to provide a water seal between the waste water pipe and the internal environment of the room. It prevents any foul odours from the drains from re-entering the room. The trap uses an easy grip compression nut, tapered rubber seal, rubber 'O' ring and a slip ring to give a secure watertight seal. It has a 600mm upstand pipe with 2 clips to hold the pipe in place.