The Kupo KG037211 Super Knuckle System is an innovative modular system that features a double-ended shell that accepts two ball joints mounted to interchangeable accessories on either side. The shell has a single knob in the center to tighten both ball joints simultaneously and complete freedom to position accessories anywhere. The Super Knuckle with Baby Receiver can support up to 17.6lbs (8kg) and includes the shell with a 5/8in Baby Receiver for attachment to accessories with a 5/8in pin, and a locking thumb wheel with a 1/4in-20 male thread on the other for cameras or other gear with 1/4in-20 female threads.