These rare Revell tires were originally designed for the Revell Chaparral 2 and Cooper-Cobra kits. They are slicks with a diameter of 13/16" and are 3/8" wire and fit a rim of 3/8" to 7/16" diameter. They have a bit of webbing from the molding process, but the extra rubber pulls right off the tire without the need for a special tool.

This is how they look before being peeled from their webbing: