Pilot IC100 Cartridge Holder

I use my trusty Pilot Metro fountain pen all the time. I try to carry some extra IC100 cartridges in my bag, but the cardboard box they come in always falls apart and I end up digging through my bag trying to find them.

I liked the look of the Apple Airpods case so I decided to copy it and re-purpose the design as a cartridge protector. I couldn't get the flip top to work like Apple did, but I used 4 8x3mm magnets to hold the top on. This design holds 6 cartridges, or 1/2 of a box.

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