<VV> In Wisconsin they are called colloctor plates

[DON W HILTPOLD JR]

Any car, truck, motorcycle that is 20 years or older can be registered as a collector. This is a one time register. The only restriction is you can't drive it in the month of January. You get a plate number and as you add cars and register them as collectors you retain the same number and you get a letter prefix A, B, C and so on. You also have to have regular registration on a vertical as well. 
Don Hiltpold