100% cotton. Size tag is missing but it is measuring like a medium in this style when I compare measurements. Please double check measurements below to make sure it will work for you. Pit to pit: 21” Waist: 17.75” Length: 54” Features: straight leg, full front zip, button tabs at waist and ankles for a customizable fit, front, side and back pockets, thick material. Condition: Pre-owned, excellent condition. Feel free to ask any questions.