Waterman 52 1/2V Question

[shalitha33]

I have one Waterman 52 1/2 v marked as SB on the back of the barrel. is this some one putting custom personalization at the end of the barrel or does it mean something? Length wise its slightly longer than the BHCR version. Unfortunately i don't have another cardinal pen to compare. "B" is half bent and the letter size and thickness is the same as the rest of the lettering.

Any info is greatly appreciated

Edited August 19, 2019 by shalitha33