Tamiya 70203 3-Speed Transparent Motor Gearbox Kit  [70203]

Transparent Tamiya 70203 gearbox for practical hobby use

The Tamiya 70203 Low-Current Motor Gearbox is a compact unit for hobbyists testing gear behaviour and energy sources. It accepts both battery packs and compatible solar panels, making it adaptable for hands-on experiments.

Construction and selectable ratios

Built from clear ABS, the gearbox lets you observe gear engagement and motion. It has three gears to choose from: 12.7:1, 38.2:1, and 114.7:1, which cover a wide range from speed-focused to torque-focused setups. A 3mm hex drive shaft and crank plates are included, and those plates can serve as simple wheels if required.

Compatibility and mounting

The case features 35mm fixing holes to fit Tamiya universal plates, so integration into custom frames or kits is straightforward. Use it for small robotic platforms, drive demos, or solar-powered builds that need a compact gearbox stage.

Power options to consider

Operate the gearbox with alkaline cells between 1.5 and 3.0V or with solar panels rated at 0.5V or 1.5V. Note that batteries and panels are sold separately to let you match supply to your application.