This is a gray bag that came with the purchase of a Carbon Mac hard case. It seems to be for dust protection or to prevent scratches. It's made of a thin material. I think people who want a large bag for dust protection can also use it. It's a bit niche, but I'm listing it because I think it's a product that people who use it would want. The price includes shipping (210 yen) and fees. Thank you for looking.