Product details:

The IN00 Single Action Ball Head has an Arca-type compatible quick-release system with an included PU50 QR plate. It can hold up to 11 lb, stands 3" high, and weighs 7.4 oz. A large locking knob controls the ball's motion and the 360 panning. A numbered scale on the base helps you accurately repeat pans, and a bubble helps ensure that the head is level to the horizon.