Children electric car gearbox
550 Middle gear upgrade to metal teeth, stronger and more durable !!!
Note:
The speed faster and the torque smaller, In turn, The speed slower and the torque greater
If the motor speed more than 10000 rpm, must to be dual drive
This gearbox left and right there is no difference, change the positive and negative can change the direction of the gearbox
550 Torque greater than 390