Simply measure the outside diameter of your tyre as well as the tyre's tread width/depth, to find the right size cover for your vehicle. (If you cannot access your vehicle to do this and only have a Tyre Code as reference.
Although these Covers have been described as RV wheel covers, they can, of course, be used on any stationary/stored/parked vehicle. For caravans, camper vans, motorhomes and camper trailers - vehicles that can go for long periods where they are not used daily - wheel covers are an effective solution towards preventing embrittlement and cracking of tyre rubber, typically caused by harmful UV.