You can also refill the disposable cartridges with a syringe. The not-sharp variety for like irrigation or whatever are the best. Just be careful. Good writing!
When I do this, I seal them up again with a hot glue gun. Then I can put a few of them into my pencil case. You do have to be careful to not bump them around too much though — I did once have one of them leak when I was new to doing this (the benefits of nigh everything I own being black, I suppose)
Edit:
You can also refill the disposable cartridges with a syringe. The not-sharp variety for like irrigation or whatever are the best. Just be careful. Good writing!
When I do this, I seal them up again with a hot glue gun. Then I can put a few of them into my pencil case. You do have to be careful to not bump them around too much though — I did once have one of them leak when I was new to doing this (the benefits of nigh everything I own being black, I suppose)