Assemble a Single Gearbox (4 Speed) with this Educational Construction Kit from the Tamiya GeniuSeries Suitable for Ages 10 & Older. This set can be assembled for 1 of 4 different gear ratios: 12.7: 1, 38.2:1, 114.7:1, 344.2:1 Hexagonal shaft. Motor cover and crank arm. Durably molded gear box case, gears and pinion gears. FA-130 type motor included with a torque of 3V. Detailed assembly guide. (1) Single Gear Box Assembly Screwdriver Hobby Knife (RMXR6909) kr9/27/05 ir/kh &