Ok, I have a friend who wants a pen, but he likes the Cross 8521 refills. Does anyone know if there are any kits that use this refill or what refills this is compatible with that I could just use another kit and swap this out?
That was my first thought as well just based on how it looks. If you have any completed rollerball pens just try to see if it fits and works. I replace most of my standard rollerball cartridges with a Pilot G2 ink refill because I too prefer a gel ink.