This compact, inexpensive plastic gearmotor (brushed DC motor with a 180:1 reduction gearbox) is well suited for use in small robots. While intended for operation at 4.5 V, it should run comfortably in the 3 V to 6 V range. The gearbox has a 0.38″-long, 3 mm-diameter D-shaped output shaft that is offset from but parallel to the motor shaft, and a built-in safety clutch helps protect the gears from excessive loads.
Key specs at 4.5 V: 80 RPM and 80 mA free-run, 30 oz-in (2.2 kg-cm) and 0.8 A stall.
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