This kit includes [2] front wheels with a rim (you can add a rubber O-ring tire on the rim but it is not included and not required). In addition, [2] back wheels with a rim and a built-in gear with a 2-gear ratio. The built-in gear fits a 2mm toy motor shaft and matches the big back wheels. Finally, the kit includes [3] axles (you can also use 1/8" axles available for wheels).

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