Tamiya Double Gearbox Kit.
Tamiya’s 70168 double gearbox packs two independent gear trains into a compact and affordable package that is great for small mobile robots
Two FA-130 type motors are included.
Each side can be assembled to have one of four gear ratios: 12.7:1, 38:1, 115:1, or 344:1.
The kit includes two motors and all gears and parts to build any of the four possible gear ratio configurations (12.7:1, 38:1, 115:1, and 344:1).
Although it is not typical, it is possible to assemble each side with different gear ratios.
There are two possible output axle locations (for any given gear ratio, only one output location is possible).
The low-voltage motors run on 3-6 volts and draw up to a few amps, making them perfect candidates for the Pololu Orangutan LV-168 robot controller Product Code 775, which incorporates these low-voltage motor drivers, would be a great control center for a robot using these motors.