Rancilio Rocky / MD40 / Obel Bregant 50 mm (suitable for Junior and Roma models only) espresso grinder burr set. Stamped on the back with the Rancilio symbol and "M.15". For Rocky users: the burr mounting screws reportedly get VERY tight and may strip when you try to remove them. You may want to consider purchasing an extra six, part number MR_25.
WARNING: This product can expose you to chemicals including lead, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.p65warnings.ca.gov.