Thank you for viewing. This is a Pentel refill. It's a discontinued refill. It has been stored by an individual for a long time. Since it is unopened, we cannot confirm its usability, so please be aware of this beforehand. Because it is a discontinued product, it cannot be exchanged. Returns are also not accepted as it is an unopened item. Please purchase only if you understand this. Please make sure to check in advance if it is suitable for your ballpoint pen. Thank you.