The Ergodyne Performance Cooling Baseball Hat features an evaporative cooling sweatband and lining that wicks sweat and moisture when worn dry and provides immediate cooling relief when worn wet. Vented back panels increase airflow for breathable comfort and an anti-odor treatment makes for fresh all-day wear. The black reflective logo, piping and hook and loop closure enhance visibility in low light conditions while remaining low-profile for daytime wear. One size fits all, this cooling baseball cap features a hook and loop closure for an adjustable fit. To activate, run or soak the interior of the hat in water until saturated, wring out excess water and wave to activate with airflow; the evaporative cooling process begins instantly and lasts for hours when worn in environments with suitable airflow. If worn dry, the moisture-wicking fabric draws perspiration away to keep you dry. To reactivate, simply rewet. This baseball cap is ideal for construction, landscaping, roofing or anyone working in the heat. It can also be used to reduce the risk of heat stress for outdoor recreational activities.