Rack and pinion gear system for smooth, quick operation. Self-locking worm gear. Replaceable handle. New comfort grip. Independent caster bearing provides easy castering. Easy installation. Zinc plated steel tubing and cast rack provides for years of trouble-free service. Up to 24" of lift. 6" reinforced poly replaceable wheel. Fits trailer tongues up to 3 x 5". Made in USA. Max Load 750 lbs.