Rock-N-Roller R9 Multi Cart Mighty With Steel BearingsThe R9 "Mighty" delivers robust results in an ultra versatile package, setting a new standard for ergonomic, all terrain performance. R9 instantly transforms into any of 8 configurations, making it ideal for moving medium to large loads across unpredictable terrain. Outfitted with 6 x 2 Groundglider front swivel casters and rugged 8 x 3 Groundglider no flat rear wheels, both sets of wheels are mounted on steel ball bearings for added durability. The