This is a sharp pencil made from Karin瘤杢 (Karin burl) wood by Kobo Setsuri (工房楔). Unlike the standard pencil by Setsuri, this one uses metal fittings from Kato Kinzoku (加藤金属), and you can also purchase the separately sold KATO201 ballpoint pen fittings to use it as a ballpoint pen. For detailed instructions on how to make the change, please watch the video on the Kobo Setsuri official YouTube channel, "Setsuri Channel" (楔チャンネル). Recently, Kobo Setsuri has been selling fewer pens with KATO201 fittings. To prevent swapping, returns and exchanges are not accepted after purchase. Instant purchase is OK.