There's a small "M" written on the inside by myself. Purchased new at a GU store. Worn once or twice and washed at home. To make the size easier to understand, I wrote "M" with a permanent marker on the inside (see photo 3). However, there's no noticeable fading or stains, and I think it can still be worn. Clean GU black pants, size M Comfortable to wear with 100% cotton material. - Brand: GU - Model Number: 321-260344 - Size: M - Color: Black - Material: 100% cotton Thank you for viewing. Color: Black系 (Black-based) Stains, tears, odors, etc.: None