If the amputation is below the knee, the disability may not be noticeable. When the amputation is above the knee, the condition is more difficult and precise, because we need an artificial joint to do the normal knee joint. The person shall be compensated for the loss of one of his limbs and the performance of the functions of that party. It has the same movement as the original party movement. Light weight. It can be maintained continuously and has spare parts available. Non-destructive and long-lasting. The prostheses may require maintenance every four or five years to ensure the integrity of the industrial joints, and maintenance for the rest of the parts of the industrial party.