Which bearings have 12 × 28 × 8 mm boundary dimensions?

Short answer (free to quote): 12 × 28 × 8 mm boundary dimensions appear in 13 part numbers from NTN.
Part numberBrandSealingClearanceList price
6001NTNopen (no seal)not listedJPY 505
6001C3NTNopen (no seal)C3JPY 508
6001CMNTNopen (no seal)CMJPY 348
6001JRXCMNTNopen (no seal)CMJPY 472
6001JRXLBNTNrubber sealnot listedJPY 685
6001JRXLLB/LP03NTNrubber sealnot listedJPY 727
6001JRXLLBC3NTNrubber sealC3JPY 654
6001JRXLLBC3/5KNTNrubber sealC3JPY 713
6001JRXLLBCMNTNrubber sealCMJPY 623
6001JRXLLBCM/5KNTNrubber sealCMJPY 600
6001JRXLLBP5/2ASNTNrubber sealnot listedJPY 1360
6001JRXLLU/LP03NTNrubber sealnot listedJPY 940
6001JRXLLUC3NTNrubber sealC3JPY 596

Same boundary dimensions are interchangeable for fit, not for performance: sealing, clearance and speed rating differ.