Topic summary
Overhaul hook ball
Extracted from the Wikipedia article Overhaul ball.
An overhaul ball, also known as an overhaul hook ball or headache ball, is a heavy weight that is attached to the end of a crane's cable, above the lifting hook. It is used to keep the cable under sufficient tension even when no load is attached. Although commonly spherical as the name suggests, overhaul balls may also be ellipsoidal or cylindrical.