U) Tires must be lawn tractor tires. No Snow Hog, tiller, A.T.V, commercial mower or performance compound or competition kart tires.
...12) Wheels must be the same size on each axle, of any origin, made of metal. No dual or tandem wheels.
In USLMRA tires are to be of lawnmower origin (F/X allows kart tires) but the rims can be of any (trailer, golf cart, kart, mower) origin.