J.S. Staedtler MARS no. 4290
This is a J.S. Staedtler MARS no. 4290 chased piston filler that needed a new cork gasket. I made a new one using the same procedure as I used on this pen.
The nib is a “Parlament” and not the original Mars – something to keep my eye out for in the future. In the meantime, the nib might migrate to the Parlament pen on this page.