... factory,worm screw Features:1) name:cnc worm,cnc worm gear,cnc worm wheel2) material:brass, copper ,steel, alminum 3)Color ... ,12 years manufacture experiences1,Worm gears are used when large gear reductions are needed. It is common for worm gears to ... interesting property that no other gear set has: the worm can easily turn the gear, but the gear cannot turn the worm. This ...