We have produced a lot of pens during the several decades we have been in business. We reached the 12th model of our Classic Pens a decade, which we called "Gen 12", which is still the basic frame we use today. We've modified several things since then, so this chart refers to the family of Gen 12 pens, of which there are four members.

If you are unsure of the identification of your pen, send a picture of the middle section of the pen to support@ackermanpens.com. The middle section where the front of the pen unscrews from the back. Make sure to include the flange around the pen in your photo. In most cases this will display cross-hatching marks, also called "knurling". We use these marks to identify each model.

If you need help, send a photo to contact pen-id@ackermanpens.com