608ZZ (8 x 22 x 7 mm) Ball Bearing. This is the classic “skate” bearing. Used in the majority of printers either on extruder idlers, shaft supports, belt idlers or in some linear carriages (such as SeeMeCNC’s Cheapskate bearings). Also typically seen on Z axis lead screw alignment plates.
Outer Diameter: 22mm
Inner Diameter: 8mm