1.There is no obvious plane of sciatic support, and the receiving cavity accommodates and supports the sciatic bone from the medial and posterior sides. 2.The inner and outer diameter of the receiving cavity is quite narrow, while the anterior and posterior diameter is quite wide, and it becomes a longitudinal oval, so that the blood vessels and nerves at the femoral triangle are effectively avoided to be compressed. 3.The lateral edge of the receiving cavity is higher than the greater trochanter, so that the femur is kept in the internal retracted position, which increases the lateral stability of the receiving cavity. 4.In addition to using the sciatic inclusion and the lower part of the lateral greater trochanter for support, the receiving cavity also mainly uses the soft tissue and femur for weight-bearing, so that the force is distributed over the entire surface of the residual limb. 5.The point of action of the joint force on the receiving cavity tends to be close to the center of the hip joint, which makes it closer to the natural physiological state. Therefore, it is more comfortable to wear and easier to control the prosthesis, especially for the elderly and amputees with circulatory disorders.