A ball valve is a valve with a spherical disc, which is the part of the valve that controls the flow through it. The sphere has a port through the middle, so that when the port is in line with both ends of the valve, flow will occur through it. When the valve is closed the port is blocked, not allowing the flow through. A ball valve is considered to be in the same “family” as the butterfly valve and plug valve, which is referred to as the “quarter turn valves” family.
Koss Industrial offers a wide variety of these valves including the brands TRIAC and Jamflow.