When you purchase the Bosch Meat Grinder attachment for the Universal mixer, it includes a 4.5mm disk, a good size for making hamburger. (The millimeter size refers to the diameter of the holes in the disk.) The small 2mm disk is for mincing. For large chunks, use the 8 or 13mm disks.
Meat grinder disks are also referred to as meat grinder plates This 4.5 disc will do hamburger, mincemeat, relishes etc.