Dimensions and geometric tolerances Unless otherwise specified, the tolerances of radial rolling bearings conform to DIN 620-2 (ISO 492), and the tolerances of thrust rolling bearings conform to DIN 620-3 (ISO 199), Figure 1. The accuracy grade is PN. For higher precision bearings, the tolerance values u200bu200bare limited to P6, P5, P4 and P2. Please refer to pages 29 to 32 for the data tables of the various tolerance classes. High-precision bearings High-precision bearings do not use standard tolerance classes, but are produced according to tolerance classes P4S, SP and UP. These tolerances are listed in the product description of the JAF precision bearing catalog, please refer to TPI120, high precision bearing with combined load. Measuring methods The testing methods of rolling bearings are in accordance with DIN 620-1 and ISO 1132-2 standards. More detailed measurement method information is given in catalog TPI138, THK rolling bearing tolerances, definitions and measurement criteria. TPI bearing samples can be ordered through the Internet. Tolerance symbols and defined tolerance symbols of machine tool spindle bearings comply with the tolerance characteristics of DIN 1132 and DIN 620 standards. d Bearing nominal inner diameter dmp Deviation of average inner hole diameter in a single plane d1mp Deviation of average diameter of the large end of the tapered inner hole Vdsp Single inner hole in a single plane Diameter variation Vdmp Average inner hole diameter variation D Bearing nominal outer diameter Dmp Average outer diameter deviation in a single plane VDsp Single outer diameter variation in a single plane VDmp Average outer diameter variation B Inner ring nominal width Bs Single inner ring width deviation VBs Inner ring width variation C Outer ring nominal width Cs Single outer ring width deviation VCs Outer ring width variation Kia Set bearing inner ring radial runout Kea Set bearing outer ring radial runout Sd Inner ring end face inner hole runout SD Outer ring outer surface busbar to the reference end face runout Sia Axial runout of the inner ring of the complete bearing Sea Axial runout of the outer ring of the complete bearing Si Change in thickness of the shaft ring Se Change in thickness of the seat ring T Nominal height of one-way thrust bearing T Tapered roller bearing assembly height