I used these on my 1965 Oldsmobile 442 with wire wheel covers. The plastic valve stem expanders that were on the valve stems didn't work at all and I couldn't check tire pressure or add air to the tires. They solved this problem as the standard tire pressure gauge seals well, doesn't leak and reads accurately and I can easily add air to the tires. You may have to apply a lot of pressure to get air in the tires. I would suggest buying two packs (they are inexpensive) as I have had trouble using one. One didn't work on a valve stem so I had to thread it onto another valve stem and it worked. The availability of spare parts excludes the possibility of using one or more tires without an extension. They will not accept a valve stem cap. These are grooves, not threads, on the end of the shank. Definitely four stars.