Sorry if a dumb question but is this a rollerball or ballpoint pen?
It says; " The EDK is also compatible with any standard Parker-style ballpoint refill. " but I believe the Schmidt refill mentioned is a rollerball.
SilvermountainThe EDK ships with a Schmidt P8126 (black), which is a rollerball cartridge, but will also accept will accept any Parker style ballpoint refill, including the Fisher Space pen refill, a pressurized ballpoint that will write at any angle -Fisher refills are shipped with a Parker adapter. I favor the Fischer because it is waterproof and will write on wet surfaces.
If you prefer gel cartridges, the Karas Kustoms Retrakt accepts the Pilot G2 refill (with its huge range of colors and widths) or Parker ballpoint compatible refills (with adaptor or spacer).
EDK: https://karaskustoms.com/pens/edk.html
Retrakt: http://karaskustoms.com/pens/retrakt-668.html
If you prefer gel cartridges, the Karas Kustoms Retrakt accepts the Pilot G2 refill (with its huge range of colors and widths) or Parker ballpoint compatible refills (with adaptor or spacer).
EDK: https://karaskustoms.com/pens/edk.html
Retrakt: http://karaskustoms.com/pens/retrakt-668.html