Tamiya’s 12-speed multi-ratio mini motor gearbox features a more compact 030-form-factor brushed DC motor driving a single gear train that can be assembled to have one of twelve gear ratios: 4.6:1, 5.1:1, 9.7:1, 10.8:1, 20.4:1, 22.6:1, 42.8:1, 47.5:1, 89.9:1, 99.8:1, 188.7:1, or 209.7:1.
Tamiya 70190 Mini Motor Multi-Ratio Gearbox (12-Speed) Kit, POLOLU-1683
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