No-load Speed: 10RPM, 20RPM, 30RPM, 50RPM, 100RPM, 200RPM, 300RPM, 500RPM, 600RPM. Model: Gearmotor Gearbox Motor XD-42GA775. Motor Length: 66 mm + Gearbox Length（L） [The slower the speed, the longer the gearbox length.].
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