Motor Miniature D.C. Mm28. A range of miniature, circular DC motors, ideal for models and educational applications (the MM10 version has flat sides). Shaft Dimensions (L Dia.): MM28: 10.0 2.0 mm. Dimensions 30.5 x 24 mm (L x Dia). 1.5 - 6.0V range. 9,600 rpm. RoHS compliant. Sold as pack of 10.