Prefixes are used to identify components of a bearing and are usually then followed by the designation of the complete bearing, or to avoid confusion with other bearing designations. For example they are used in front of designations for tapered roller bearings according to a system described in ANSI/ABMA Standard 19 for (predominantly) inch bearings.

AR-Ball or roller and cage assembly
E2.SKF Energy Efficient bearings
GSHousing washer of a cylindrical roller thrust bearing
IR-Inner ring of radial bearing
KCylindrical roller and cage thrust assembly
K-Inner ring with roller and cage assembly (cone) or outer ring (cup) of inch tapered roller bearing belonging to an ABMA standard series
LSeparate inner or outer ring of a separable bearing
OR-Outer ring of radial bearing
RInner or outer ring with roller (and cage) assembly of a separable bearing
WStainless steel deep groove ball bearing
WFDeep groove ball bearing of stainless steel with external flange on outer ring
WSShaft washer of a cylindrical roller thrust bearing
ZEBearing with SensorMount® feature
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