... self locking, Positioning Precision, Heavy Duty, Uniform Lifting Speed, Low Efficiency, Use Infrequentl worm screw liftConfiguration: Worm Gear, Worm Shaft ... ; Medium ratio,1 turn shaft,0.5 mm stroke;Low ratio,1 turn shaft,0.25 mm stroke. * ... Accessories: Bevel Gearbox,Hand Wheel,Electric Motor,Motor Flange,Frequency Inverter,Safety Nut,Steel Cover,Rubber Belllows,Limit Switches,Couplings,Flexible ...