Here we have the Parker Jotter. Don't hear much about this pen yet the Jotter has been around since 1954 and is one of the best selling pens in the world. These pens in the picture are all current models. I just like the colors. The number four purple Jotter is the only one with any history. It is a 50th Anniversary issue, it has no feathers on the arrow pocket clip and has a 50 on the top of the push button. You can now buy refills with gel ink and in many knew colors. Parker Jotter should be in your collection.