Product Overview
The GX-Knee comes equipped with a pneumatic spring on the lateral joint to assist with knee extension during the swing phase of gait. A medial knee joint is also included to help control knee alignment. The GX-Knee is a free motion knee joint that is designed to provide extension assist, not prevent knee flexion. Available with your choice of a 75N, 125N (for standard applications), or 175N pneumatic spring.
(https://www.beckerorthopedic.com/Product/CustomFabricationServices/CustomStanceControl/318)