... , Lowering, Pushing, Pulling and Rolling Linear Motions. Worm Gear Drive Screw Jack Accessories: Protective Tube, Rubber Bellows, Electric Motor ... , Bevel Gearbox, Swivel Plate and Trunnion Base. Worm Gear Drive Screw Jack Features: * Top End: Top Plate,Clevis ... -backlash Nut Device Available. * Special Custom Design Available.Worm Gear Drive Screw Jack Materials: * Lifting Screw: steel C45 (optional: ...