The Avenger C339UH Grab Clamp with Universal Head is flexible and fast, and thanks to its pincer jaw design, can be affixed to a wider variety of round or square pipes, beams and bars than traditional clamps. It has a push-button lock for extra safety, a standard 1 1/8" junior receiver and a 5/8" stud for fixtures and gear matching those sizes. Used in TV, video and photographic studios and theaters, the Grab Clamp will hold up to 165 lb.