Features 4 screened side vents, loops woven into the sides for leaves and branches, and an adjustable chin strap and are made from a 100% cotton rip-stop material. Military Style Boonie Made With A Rugged Cotton Rip-Stop Material Loops Woven Into The Sides For Leaves And Branches Four Screened Side Vents On The Boonie Cap Offer Optimal Cooling Airflow Adjustable Chin Strap