- Adapter turns a single connection for waste water into a double connection ,- Ideal for connecting two appliances with a waste water connection to just one siphon connection ,- Made from impact-resistant polypropylene with backflow preventer ,- Backflow preventer only opens when water is draining, thus preventing water from being pumped from one machine into the other ,- Easy to fit to recessed siphons (gasket fixed onto the pipe) ,- 1 union nut, 2 x hose connection 20 - 24 mm