Pololu - 12mm Hex Wheel Adapter for 3mm Shaft (2-Pack)

These 20 mm long aluminum adapters convert a 6 mm diameter shaft to a 12 mm hex shaft that is compatible with many common hobby RC wheels. The set

12mm Hex Wheel Adapter for 6mm Shaft (2-Pack)

12mm Hex Wheel Adapter for 3mm Shaft (2-Pack)

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