The build quality and appearance of these valve stem caps are excellent, but after 10,000 miles the caps will not come off. A quick internet search reveals that this is a common problem with metal valve covers - road salt, moisture and dirt seep in and corrode the internal threads, effectively bonding the metal of the valve cover to the metal of the valve threads. Many, like me, have had to resort to a cutting tool to remove them after my mechanic told me he wouldn't touch them for fear of damaging the valve stems and having to replace them for $40 each. All because I thought the metal caps looked better than the standard plastic ones. I cannot recommend these or any other metal caps.