BO (battery operated) gear motors are the most popular choice for small robot cars. This motor has a dual shaft, so you can mount a wheel on one side and an encoder or second attachment on the other, with a plastic gearbox that is lightweight, low inertia and able to absorb shock and vibration.
It works with motor drivers like L293D and L298N and compatible robot wheels. Great for school projects, STEM kits, robotics clubs and hobbyists.
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