Self: 100% cottonLining: 100% polyester. Spot clean only. Back adjustable velcro strap. Front embroidered design. Side reflective slogan with patch detailing. Ventilating eyelets at top. Back embroidered logo. Brim measures approx 3" in lengthOS measures approx 23" in circumference. Made in China. Our Style No. MROS-MA10. Manufacturer Style No. 1217WP13200.