An Equilibrium Brass Ball Valve is a type of float valve for cisterns and cold water storage tanks that is designed to eliminate water hammer and operate quietly by balancing the water pressure on both sides of the piston. They are a more robust and reliable alternative to standard ball valves, especially in larger commercial or domestic properties. 
Key Product Information
Equilibrium brass ball valves are available from several manufacturers, including EBCO, Masefield Beta, and JTM. 
Function: They use a hydraulically balanced closing action to provide a fast, quiet shut-off of water flow, even with high water pressures up to 5 bar (72 psi) for the full bore versions.
Construction: The body is made of high-quality brass or gunmetal for long-lasting durability and resistance to corrosion.
Connection: They typically feature a standard 1/2" BSP or 3/4" BSP threaded tail for connection to the water supply.
Float Type: These valves must be fitted with a copper ball float, as lightweight plastic floats may impair the action of the valve