When finding main bearings on our website, our numbering system works as follows:

The 1st number in the part number is �the Thrust Size of the case;
which is the dimension between the 2 flanges on the rear bearing that fits on the case.
Please measure the case for this measurement!
111 - identifies a std thrust size (standard size is .865)
112 - identifies a 1st oversize (.825)
212 - identifies 2nd oversize (.785)

The 2nd number in the part number is the over size bore that the case was align bored to.
we offer bearing in the following overs sizes.
.020 equals 20
.040 equals 40
.060 equals 60

The 3rd and final number is the crankshaft main journal measurement!
STD = 2.165
10 = 2.155 (.010 under)
20 = 2.145 (.020 under)
30 = 2.135 (.030 under)
40 = 2.125 (.040 under)