This Hozelock 2181 Non Return outdoor tap connector is an all-plastic double check valve, which connects to outside taps and prevents backflow into the mains water supply. It is suitable for all 1/2 inch, 3/4 inch and 5/8 inch BSP taps. Hozelock 2181 Non-Return Valve Tap Connector 1/2 - 5/8In Bsp in Yellow
