Pocket Watch On Chain

What type of pen is this?

everything I know about this pen is that it can enter into 'gold' and when you pull the end comes out the side writing, similar to the modern pen cross. This pen was given to my father by the mother of my father. Around when they were hired 20 + years). I knew that men in the early and mid 1900s has brought this on their chain pocket watch. Thank you very much!

most of the pens in 1900 were pens or homemade dipped in ink

Stauer Skeleton Dial 2-Tone Pocket Watch with 14-1/4 Cha…