CB Design CBD0690 1:24 Classic Steel 20 x 10.5mm Wheels for 3/32" axle with center rib are based on our popular 1:32 Classic Steel Wheels. They are intended primarily for scratch builders. Designed for use with Paul Gage H&R Narrow (center rib) urethane tires. Note: There is also a version designed for 1/8" axles - be sure to order the correct version. Dimensions: Diameter (Center Rib): 20.0mm Overall Width: 10.5mm Center Rib Width: 5.5mm Hub: No (hubless) Axle Diameter: 3/32" Package contains one (1) pair of wheels. Why Offer Two Axles Sizes? Many 1:24 scratch builders, particularly those trying their hand at scratch building a 1:24 car for the first time, already have a significant investment in 1:32 parts such as axles, gears and bushings that are designed for 3/32" axles. The 1:24 Classic Steel Wheel for 3/32" axles gives these scratch builders the option to leverage their existing investment in 1:32 parts. On the other hand, the 1:24 Classic Steel Wheel for 1/8" axles lets scratch builders who already have an investment in parts designed for 1/8" axles use those parts.