... Pushing, Pulling and Rolling Linear Motions. Worm Gear Drive Screw Jack Accessories: Protective Tube, Rubber Bellows, Electric Motor, ... Top Plate,Clevis End,Threaded End,Plain End and Forked Head. * Single Unit, In Pairs or Multi-Units Arrangement ... Available. * Special Custom Design Available.Worm Gear Drive Screw Jack Materials: * Lifting Screw: steel C45 (optional: stainless steel) * Worm Gear ...