Mabie Todd didn't refer directly to this little Swan as a ladies pen, although the way it was advertised certainly made it clear the this was their intended market.
The most unusual thing about the pen is the clip, a stepped, art deco looking affair similar in shape to that found on some later Waterman's pens. It never appeared on any other Mabie Todd offerings.
The pen appeared in 1939 and remained in production for only about a year, stopping when the wartime restrictions were imposed and not continued thereafter. It is quite a rare pen.