55 mm x 120 mm x 49,2 mm ISB 3311 ATN9 angular contact ball bearings

Various angular contact ball bearings NTN BEARING CORP. types and sizes to accommodate your 55 mm x 120 mm x 49,2 mm 55 mm x 120 mm x 49,2 mm ISB 3311 ATN9 angular contact ball bearings requirements. 0.079 Wall Thickness (S3)

What is 3311 ATN9 bearing interchange？