Trail Running Main Fabric: 100% Cotton Four-panel construction for a snug fit and comfortable wear Ultra-lightweight fabric for easy storage in a pocket or trail running vest during runs Stretch softshell fabric that is breathable and lightweight, with perforated ventilation holes at the back for enhanced airflow and quick heat dissipation Sweatband treated with silver-ion odor-control technology to help prevent odor buildup during extended wear S-shaped adjustable buckle for a customizable fit Head Circumference: 59 cm