The spring compressor fulfills its purpose properly. I had him today use in my C Corsa, of course, there are better versions, but ... (New springs, new shock absorbers, new summer tires) so much the choice indicated on this product At first I was a bit skeptical, but after the first spring I was fully motivated. The tensioner keep their promise. However, the springs had a Drahtdurchmeser of 11mm. For larger FZ (BMW, Mercedes, etc.), the tensioner might falter. Please read!