Miniature Thrust Ball Bearings Set 3 parts, 2 Washers and Retained Bearings.
Miniature thrust bearings can withstand axial or thrust loads only. There are separate types of miniature thrust axial bearings with either flat races or washers incorporating a groove or raceway for heavier loads. The grooved type have one washer with a slightly larger bore to allow it to locate in the housing while the other washer has a smaller OD to locate on the shaft.
The bore (d dimensions) of one washer in the set will conform to the data in specs Catalog charts.
The bore (d dimension) of the matching washer will be roughly .007" larger, because it is a clearance hole for the shaft.