Hydraulic Cyborg Hand KitA fun to build hydraulic cyborg hand that simulates the movements of your hand and fingers. The three fingers and opposable thumb have adjustable joints, which enables you to pick up large objects like a bottle of water to smaller items like a pen. It can fit left or right hands of different sizes, and uses hydraulic mechanical power so no batteries are needed. This makes a great gift and can teach kids how hydraulic systems work.