Gray color. The location and number of the serial number will be provided after purchase. Comes with a storage bag. Size: The longest part of the top is approximately 48-50cm wide; the height and depth vary depending on the contents, so they are not specified. There is a zippered "lid" cover to prevent the contents from being seen, and when closed, the "lid" also has a zippered pocket, making it convenient to take out items like a pass or smartphone. There is a snap in the center. If you open the lid and store it, it transforms into a casual tote bag. There is a pocket inside. It is very light for its size. It has been used, but I think the inside is clean. I don't think there are any noticeable scratches, frays, or stains, but please forgive any oversights. Please take a close look at the images. We are waiting for your consideration if you agree to no returns or claims.