Brass ball valves are devices that are used to regulate the flow of any kind of fluid. A fluid can be any form of gases, solids, liquids. Ball valves control the flow of fluids by closing, opening, and obstructing various lanes. http://www.qtellsocialnet.com/192/posts/63-Home-and-Family-/2151--Bathrooms/140285-Benefits-of-Brass-Ball-Valves.html