I bought a complete set of NOS "Isuzu wheel center caps" off of eBay that looked identical to the caps on the 18" VehiCross wheels. They did not fit. Too big. I cannot find them now, so I cannot verify the diameter of the caps. Maybe someone else has a metric ruler and can tell you the diameter of the VX caps. The ones I bought are about a 1/4" too big. I still have them if anybody needs them for their other Isuzu wheels.