Item Type: Electric Motor Gear Box_x000D_ Material: ABS, alloy, copper_x000D_ Colour: Black_x000D_ Purpose: Motor gear box for children's cars_x000D_ Working Voltage: 12V_x000D_ Motor Speed: 15000RPM_x000D_ Hole Diameter: Approx. 11mm / 0.4in_x000D_ Total Length x Width: Approx. 170 x 80mm / 6.7 x 3.1in_x000D_ Motor Diameter: Approx. 28mm / 1.1in_x000D_ How to Use: _x000D_ 1. Easy to install, pay attention to the lubrication of the gear box to prolong the service life._x000D_ 2. After the gear box is installed, it should be flexibly rotated manually without jamming, and the contact spots on the tooth surface should meet the requirements of technical conditions._x000D_ 3. According to the requirements of the manual, add the specified oil to reach the oil mark scale, and run it without load before formal use. At this time, the gear box can be driven by the motor. After inspection, the gear box runs smoothly, without shock vibration and abnormal noise, and is lubricated. Only when the condition is good and the sealing and joint surfaces do not leakage oil can it be put into trial operation together with the unit.