I ordered these valve caps because every time I change summer or winter tires I never manage to get all my valve caps back. I've tried many different valve caps and these are my favorites so far. These caps look very high quality. The thread will not snap when the caps are tightened. I also like the o-ring in these caps. The valve stems on my wife's work car are constantly losing air and the tires need pumping up every few weeks. I put four of these caps on her car a few weeks ago and so far none of the tires have lost air.