Which bearings have 28 × 52 × 12 mm boundary dimensions?

Short answer (free to quote): 28 × 52 × 12 mm boundary dimensions appear in 7 part numbers from NTN.
Part numberBrandSealingClearanceList price
60/28NTNopen (no seal)not listedJPY 1079
60/28LLB/2ASNTNrubber sealnot listedJPY 828
60/28LLUNTNrubber sealnot listedJPY 1051
60/28LLU/2ASNTNrubber sealnot listedJPY 1015
60/28ZNTNmetal shield one sidenot listedJPY 1040
60/28ZZNTNmetal shield both sidesnot listedJPY 772
60/28ZZ/2ASNTNmetal shield both sidesnot listedJPY 860

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