Product Overview
The Variloc® Positioning Joint is an adjustable locking rotary joint that combines strength with ease of operation. The Variloc® Positioning Joint is positively engaged by high strength locking pins, which can be instantly disengaged by a push-button mechanism, allowing the joint to rotate.
(https://www.beckerorthopedic.com/Product/KneeJoints/1000KneeSeries/1800)