This fountain pen is a Vacumatic made by Parker in about 1940. It is their topline model with the blue diamond clip. Parker used a small blue diamond placed at the top of a clip as a sign a pen was guaranteed. Parker guaranteed pens with this blue diamond for the lifetime of the original owner. This pen has the Parker arrow shaped clip. It is the golden arrow striped design. The body is black and the stripes on this pen are golden. The outside of this pen is in good condition. I have not tested the usability. This is a lovely collectible fountain pen.
Parker blue diamond Vacumatic fountain pen