This is a short-sleeved top made of thin material. I wore it in the summer until a few years ago, but I haven't worn it in the past year or two, so I'm selling it. ◯ It's a size M, but I feel like the neck and chest area are made a little smaller. The neck is tight because it's the type that fastens with a button at the back of the neck. ◯ It's a women's item, but it's a size that could probably be worn by someone around middle school age. ◯ As you can see in photos 4 and 5, there are a few loose threads. They're not very noticeable, so it's still in good condition to wear.