Ball valve

quarter-turn valve which uses a hollow, perforated and pivoting ball to control fluid flow

A ball valve is a kind of valve that has a ball in it, and the ball has a hole in the middle.

Cut-away view of a ball valve: 1) body 2) seat 3) floating ball  4)  lever handle  5) stem

When the valve handle turns one way, the hole opens up the valve and water or gas can go through.

When the valve handle turns the other way, the ball blocks the water or gas, and the valve is closed.

Ball for a titanium ball valve