I have found Jinhao pen that can have configuration of fountain pen with nib and rollerball pen. See attached picture where you will see Jinhao Dragon's Offspring or Jinhao 888. I am not sure whichever is more correct as there's also NJ39, 40 and 41... Left one I saw in one seller's eBay store and right one in different seller's store but I want to buy former (rollerball pen) from second seller who has only fountain pen. What I am trying to understand is do these pens have some kind of compatibility where fountain pen can be converted into rollerball pen? I mean I understand that both have different ink containers and nib cannot be interchanged with tip but I am sure I can take out ink container with nib from fountain pen and put rollerball refill inside. Correct?
Consequently can rollerball pens and ballpoint pens be interchangeable i.e. I keep using same barrell, cap but now can turn pen into gel pen with gel refill or ballpoint refill?
I also liked X250, X450 and X750 but will there be different variables provided I want to do similar conversions I mentioned above?
Appreciate your help to enlighten me.
Edited by TechnicGeek, 13 September 2015 - 13:59.