Grohe Universal Non-Return Valves - 14165Grohe Universal Non Return Valves 14165 Universal non return valve set designed to help prevent backflow in compatible GROHE plumbing and shower applications. Features Universal non return valves for compatible GROHE systems Helps prevent water backflow for reliable plumbing performance Designed for use in shower and hand shower applications Durable construction for long lasting reliability Precision engineered for secure fit and dependable operation