Hey Folks. I picked up a modern pen branded Mix And Match. It has a printed sticker that reads "Mix and Match -It's More Than a Product-Stationery Team Holland" The nib is a folded nib that is unmarked yet resembles old Stypen nibs. The pen came with a double ended long cartridge which looks like it fits Parker pens on one end and something else on the other end. The other end seems shaped like an International cartridge, yet lacks the glass ball at the end. What I do not know is which end fits into the pen. Does anyone know the answer?