Hi all, has anyone used any of these? You drill the inside dia valve stem hole in your rim and fit this plate with round nut/bolt assy in its place, it is designed to stop the tyre slipping around the rim and making that horrible bump in that area, quite a good idea really, I wish he had 2 now. The next set of tubular wheels I get built I will use them on. If you have any comments please post to the list, if you want to look at a pic go to the auction I bought these from........regards wayne davidson Invers NZ.........