Spherical Washer, Bottom Washer Inside Diameter 7.2 mm, Minimum Thickness 4.2 mm, Pack Size Small Pack, Rockwell Hardness C40, Spherical Washer Type Spherical Washer Assembly, System of Measurement Metric, Top Washer Inside Diameter 6.4 mm, Top Washer Outside Diameter 12 mm, 1 Pair.