The Aqua Stop connector has an internal valve that stops the water flow when an accessory is disconnected. Saves water in the garden because it stops the water flow. Suitable for use with all 12.5mm 1/2in and 15mm 5/8in hose. All internal parts are made from ultra tough engineering plastics for a long leak free life. The hose is firmly connected thanks to barbs that connect with the inside and outside of the hose. The connection to the tap is guaranteed secure up to 10 bar.