Choosing the Right Wholesale Brass Ball Valve for Your Plumbing System Wholesale brass ball valves are mechanical devices used to control the flow of fluids within plumbing systems. They consist of a hollow brass sphere (the "ball") with a hole (the "bore") through its center. A handle or lever is attached to the ball, allowing it to rotate within the valve body. When the handle is turned perpendicular to the pipe, the ball blocks the flow of fluid,...