Engineer Ian Davis built his own mechanical prosthetic when his medical insurance did not cover him, it functions without batteries or electricity

https://t.co/kW92jbK7Ik https://video.twimg.com/ext_tw_video/1757456938126761984/pu/vid/avc1/720x748/7WvF22lsNkzXIiO9.mp4?tag=12