This unique Bearing-Balanced Fluorite pendulum is designed by George Goodenow, this pendulum is BEARING BALANCED. That means the pendulum chain rotates and swivels on a bearing that is inserted into the top cap(chamber cover). This results in a balanced swing that keeps the pendulum point, or bob, always aligned with the chain while swinging . This movement provides an instant and sensitive response. This alignment is excellent when using charts, always pointing in harmony with the arc of the swinging pendulum.