The last thing you want to be doing when you've got a flat tire on the way to the lake is fumbling with and trying to assemble those cranky, knuckle-busting, finger-pinching conventional jacks. Instead, all you have to do is simply place the Quick Change Trailer Jack under the axle and drive forward or reverse a few inches and your trailer is automatically raised for a quick tire change. It's easy and stable for maximum safety. No moving, mechanical components to rust, bind or fail. Makes maintenance work at home - like lubricating or replacing wheel bearings - go much more smoothly. Works on all surfaces, round or square axles and tires from 10" to 15". Two-ton capacity.