Waterman date code?

When pen collectors hear "date code", they think of Parker. Other pen companies used date codes later on, but as far as I know, Parker was all on its own when it added a date code to its imprints from 1934 on. Yet the pen shown above, a Waterman/Aikin Lambert Vis-O-Pen, had what appears to be a date code, "38", on its plated stainless steel nib.

I confess that I have not paid a lot of attention to these economy-line pens, so this may be old news to others. Such codes do not appear on Waterman or Aikin Lambert nibs in gold.

UPDATE: Not a date code after all, it appears. Daniel Kirchheimer has pointed out to me that "38" is the base model number for the Vis-O-Pen line, and the number appears on all Vis-O-Pen nibs.