ITEM NAME:Gear Reduction Unit Black Prevent Car From Shaking And Stalling When Starts Description: This planetary gear reduction unit is designed for slowing down the motors when torque is needed more than speed. It fits 540 motor and 1: 10 RC car Perfect for 540 motor Slow down motors when torque is needed more than speed Sensitive in power distribution Provide smooth vehicles starting Prevent car from shaking and stalling when starts Specification: Name: Planetary Gear Reduction Unit Color: Black Main material: Steel Suitable for: 1/10 RC Car Package Size: 9 x 5 x 4.5cm / 3.54 x 1.96 x 1.77inch Package Includes: 1x Gear Reduction Unit Note: The included steel pinion goes onto your motor, then use your original pinion on the output shaft of this gear reduction unit. This product is designed for regular 540 brushed motor, its not designed to run on high power brushless motors. It will work, but it wont last a long time. SKU: DMO0008652261024550.Prevent car from shaking and stalling when starts. The included steel pinion goes onto your motor, then use your original pinion on the output shaft of this gear reduction unit. This planetary gear reduction unit is designed for slowing down the motors when torque is needed more than speed.