Noun
ballhead (plural ballheads)
A device used in camera stands, prosthetic joints, etc. to allow rotation of the attached part.
The idea of a monopod is to lighten the load but if you are adding an additional pound and include a ballhead are you not better off taking the tripod? Source: Internet
The other inherent flaw is the rubber they use on the leg locks, and also on the ballhead knobs. Source: Internet