Two DC motors & gears in a compact unit. Provides full forward-reverse-left-right action! Build with 1 of two different ratios: fast 58:1 or strong 203:1. Add your own wheel, hubs or tracks. Specifications: Size: 75 x 50 x 23 mm

It is a gear box of Techni Craft series enough, durability is that used in many robot contests machine in addition to the high accuracy of low transmission loss.Gear ratio of the four types to choose in reclassification of gear in the final stage and the intermediate, 4-speed power gear box HE is well suited for work that requires power and position change, the spur gear and exchange (10T, 12T) of the motor pinion you.Two positions can be selected as 4mm diameter output shaft of the threaded.I have also set hex hubs and crank arm. 260 type motor with.You can use the adapter parts, it can be mounted motor type 140 and type 130 motor (sold separately).

A gearbox that can choose three gear ratios by using a motor that can be used with constant current. As well as dry batteries (1.5 V to 3 V), it can operate even with a low voltage power supply of solar panel (0.5 V, 1.5 V) which could only use exclusive motor until now. The gear case is made of ABS resin. With a clamp plate that can also be used as a wheel. The output shaft is a 3 mm hex shaft. Length 100 mm. The gear box is mounted at 35 mm pitch matching the universal plate. (From Amazon.co.jp)