Ratner serial number

[safeman]

Am I right in thinking that the two serial numbers are normally the two lock numbers, when I see these they are normally sequential, but the one I am after info on has
42342
41829
BB

if anyone has an info relating to these numbers it would be appreciated.

Only the dates Gary : 42342 is 1924 : 41829 is 1925. The only interpretation I can think of for BB is Branch Bank.