Very nice pen, I got it as part of the last mystery box, but what I'm stuck wondering is, what is the empty cartridge for? I opened the pen and there were two in there, and I can't figure out why I need an empty one. Is it for shipping? Other companies don't do that, or is there some other purpose I'm missing due to my own ignorance?
ZeiredIt's not actually an extra cartridge but rather a hollow one. You can use it as a spacer with a short cartridge or you can use it to help clean the pen. Just pop it in like a cartridge and since it's hollow you can shoot water through it and out the nib for example using a bulb syringe. You can flush the pen in just a few seconds that way! (You can of course clean the pen with a bulb syringe without using the hollow cartridge, but I've found that adding it helps the process go even faster and reduces the chances of water/ink dribbling or accidentally squirting out in some random direction.)
Edit: stupid auto-correct.