This is much better than I expected for the price. We drive an SUV that weighs 5,400 pounds so it fits in an emergency bag along with a small 2.5 ton jack. The sliding mechanism allows each of the bars to be moved to the end, giving you much more leverage to loosen the compression nuts. You can then roll it up to allow the bars to align and "lock" together for easy storage. I hope I never use it on the road, but I tested it when I switched my winter tires to summer tires and it worked perfectly.