Quickly connects double check valve for fluid category 3 backflow prevention with integrated isolation JG Speedfit double check service valve ensures water only flows through in one direction to prevent the backflow of contaminants. The valves ensures that water only flows through in one direction to prevent the backflow of contaminants. Simply push the valve fully onto the pipe. To demount the connection, push the collet towards the body of the push-fit fitting and pull the pipe release. The JG Speedfit double check service valve is up to 40% faster to install than traditional methods and is easier to use in confined spaces by removing the need for hot works and tools. Designed, manufactured and assembled in the UK. Features and benefits Double check valve (Fluid Category 3) Install and demount in seconds without tools Safe flame-free installation, with no hot works, glue or flux Grip & Seal™ collet with stainless steel teeth and main O-Ring seal Compatible with Speedfit PEX and polybutylene plastic pipe (inserts required) and copper pipe Suitable for hot and cold water (not suitable for central heating)