This is a 4 wheel drive 0 gauge motor unit as shown in the pictures. It is suitable for battery use up to 4.5 volts. It is very powerful, on one 1.5volt aa battery I was unable to stop the axles from turning using my hand. It is 10cm long and a maximum of 5cm wide. The distance between the axles in width is 25 mm and the distance between the axles in length is 53mm. The axles are suitable for wheels with a 3mm hole. The axle protrudes 8mm out from the body. The distance from the middle of the axle to the bottom of the unit is 11mm. All sizes are appropriate but I have measured carefully. Please note that wheels are not included and the motor will have a white or red cover. It is a nice, simple, powerful unit.
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