An item of any peripheral shape usually having one flat or spherical surface and a centrally located hole. It is designed for applications involving moving (kinetic) loads. Except for items fabricated from bearing quality synthetic (plastic) or composed of multilayer material, one bearing surface must either have a specific surface finish designation of 32 microinch (0.8 micrometre) or less, arithmetical average (aa) (arithmetic mean deviation) or one of the following conditions: be lapped or ground; have visible or detectable means of lubrication; grooves, indentations; or self-lubrication. The thickness must not exceed 25 percent of the outside diameter of the shortest distance between peripheral flats (when thickness and/or outside diameter is designated as a tolerance dimension, the maximum dimension will be used to determine compliance). Excludes straight, tubular (without flange) items having a bearing surface(s) parallel to the axis of the bore only. See also washer, flat and spacer, sleeve.
Dept. of the Army 
Dept. of the Air Force 
Dept. of the Navy 
Portugal Classification: Thrust ball bearings
NSN 5945-00-900-3932
NSN 5998-01-056-1448
NSN 5925-01-152-4955
NSN 6220-00-007-5973
NSN 5935-01-388-0162
NSN 5998-01-655-3094
NSN 5905-01-537-0200
NSN 5945-01-422-4195
NSN 5930-00-179-1214
NSN 5965-01-035-6842
NSN 6220-01-229-5960
NSN 6105-01-075-6678