This raised rib (top) surrounds the rim with a beefy section underneath. This protects both the rim and tire from damage when rubbing against rocks. Along with the standard three-ply sidewalls of the BFGs, this is bound to be one durable tire. We checked out the new rim protector (above) by purposely bashing some boulders. We’re sure we could ruin anything if we tried hard enough, but the Center Line wheels and KM tires seemed to brush off our attempts.