H&R Racing Products Adjustable Wheelbase 1/24 RTR assembled Rolling Chassis - Wheelbase adjustable from 3 5/8" to 4 7/8" (92mm to 123mm) - Includes Hawk 18,000RPM Motor, narrow Soft SILICONE rear tires (Shore A 25 Hardness) on setscrew aluminum hubs and foam fronts, Oilite bushings, body mounting kit - Comes with inline motor mount & Parma axle gearing - recommended for plastic home track application or commercial routed track racing where no tire glue is used.