They work great. I've used them a few times when I was working on the exhaust as well as the intercooler pipes on my car. I have a 2015 VW GTI that weighs about 3000 pounds. Am I going to use them on a huge, heavy truck or SUV now? Probably no! But for my 3000 lb machine they do the job. They prevent the car from rolling, skidding and squashing/squeezing.