Nice Claup Crop Top Mint Green Brown Buttons Women’s

I originally thrifted this and I’m not sure what size it is. It fits me well everywhere but the arms which are kind of tight so I can’t really wear it. I’m 5’7” and usually wear a size medium or large. I think this would be most suitable for women’s size small or medium. The tag lists this as size F for anyone who may know what that means. It’s mint green with brown buttons the buttons are functional, not just for show. It has a deep v-neck. It is cropped. Please note that all items come from a dog-friendly house but items will be washed before being shipped out. Item is sold as-is. No returns.