These worm gear assemblies can be built to provide travel distances from inches to yards. The gear box ratio is 20:1 with the option to adjust speed or power thru a variety of lead screw pitches. The housings can be build using glass filled nylon and zinc die cast. Input worms can be either nylon or steel. Current applications include power foot rest, seat actuation for height, tilt and forward/aft movement, sofa beds and marine hatch cover mechanisms. Feel free to contact Smith Richards Inc. any time to discuss your individual linear actuator needs.