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.
unable to decode material, machined retainer fabrication method, abec no.5 standard tolerance designation, with inner and outer ring spacers special features, 0.0008 inches minimum radial and 0.0014 inches maximum radial internal clearance