Johannes Iverson owned the Miller Pen Company in Copenhagen (see this document) and patented a filling system called a “stretch-vacumatic”.
The patents are here (in English), here (in Danish), and here (in German).
This 698 is a 12-sided doric pen made sometime around 1940 in Denmark.
This pen has been completely disassembled, and a new sac installed.
Note that the blind cap does not seat completely flush with the barrel.
Item number: V201616