This single-handle thermostatic mixing valve allows you to select the water temperature for your showerhead and body/side sprays. Once set, the temperature remains constant even if the water pressure changes, like when someone flushes a toilet. Requires a separate on/off volume control.Brass Casting: Highest quality faucet material for durability & long life.Wax Thermostatic Unit: Permits shuttle valve to move between the hot and cold seats to maintain the pre-selected constant water temperature.Back to Back Capable: Hot and cold can be reversed.Spring-Loaded Check Valves: When the hot and cold water enters the fitting, both supplies pass through the spring-loaded check valves to prevent cross flow of hot and cold water. Integrated stop valves ensure easy cleaning and servicing.Adjustable Hot Limit Safety Stop: Limits the amount of hot water allowed to mix with cold. Reduces the risk of accidental scalding. Maximum water temperature limit may be reduced to 104 or 109 degrees Fahrenheit.