Serial Number On Crankcase?

[Tyler Shea]

I got a hold of a pair of Polished White/Jade lens Crankcase, and there is an extra number on the arm. It reads OO9165-03 56O17 then 125. What does the 125 mean? Thanks, Tyler

 

[RetinaBurn]

More than likely that is the earstem length.

 

[Tyler Shea]

My matte pair does not have the 3 numbers at the end. Should it have those number?