Grohe Universal Non-Return Valve 3/4" - 12510Grohe Universal Non Return Valve 3 4 12510 Universal non return valve designed to help prevent backflow in compatible plumbing and shower system applications. Features Universal non return valve for backflow prevention Helps maintain proper directional water flow Compatible with select GROHE shower and plumbing systems Durable construction for long lasting reliability Designed for smooth and dependable operation Precision engineered German