So, this jack is good but not great. It works well, but when it's going up and down, it jerks a little. It sounds like there is a shaft inside the airbag that it rides up and down on and the shaft probably has grooves in it from machining. It sounds like there is a metal doohickey inside that is riding on a shaft with little grooves on it. The jack catches and then breaks free. Not a big deal at all, but could be better. I have a old t-bird that is very low and very long. It is hard to get a floor jack under it and the airbag jack lifts it right up with little effort.