Motor Miniature D.C. Mm12. A range of miniature, circular DC motors, ideal for models and educational applications (the MM10 version has flat sides). Shaft Dimensions (L Dia.): MM12: 8.1 2.0 mm. Dimensions 25 x 21 mm (L x Dia). 1.5 - 3.0V range. 14,700 rpm. RoHS compliant. Sold as pack of 10.