BIAL-cap Military Camouflage Boonie Bush Safari Outdoor Jungle Hat Cap Material: 60% cotton, 60% polyester. Specifications: Head circumference22.4in. Adjustable chin strap ensures a secure fit,Two snap buttons help changing to another style hat Design on both sides have a vent, ventilation cooling, the head will not stuffy. Wide brim and screened side vents are sure to keep you cool in the blazing sun.