Do you mean Portawalls? They have been around since the 1950's and are a rubber like disc that fits on the sidewall of the tire and are held in place by being tucked under the rim. I used them for years when I had my used car lot and they certainly transform a black sidewall tire into a whitewall. They usually were about 2 1/2 inch wide and worked well as long as you did not hit a curb with them while parking. 4 1/4 inch whitewalls are proper for most of our full size KF cars and portawalls are not that wide as they would not cling to the sidewalls. I don't think that they would work on radials or tubeless tires and if you don't care about authenticity they are an inexpensive way to have the appearance of whitewalls. They can currently be purchased at Lucas Tire Co. They are online and have their main store in Long Beach CA. They used to be available for 13, 14, 15, and 16 inch tires.