Two single row annular ball bearings selected dimensionally to be a matched pair or set. The ring faces have been specially ground to specified offsets that will produce predetermined preload when mounted. May include a single row angular contact bearing with faces specially ground for duplex mounting.
mil-g-23827 mil spec single material response lubrication material document and classification, radial load direction, 1.3125 inches nominal overall outside diameter, 0.8750 inches nominal bore diameter, 4.0 pounds minimum and 6.0 pounds maximum bearing preload rating