Mission HydroActive MAX provides 30% greater cooling power to cool you down fast. For an instant cool, simply dip the hat in water, and wave in the air to instantly activate the cooling technology. Cooling effect lasts up to 2 hours. To re-activate, simply resoak and wave. Soft, ventilated mesh cooling zones help rapidly evaporate sweat and increase air flow where you need it most. Adjustable design with hook and loop strap provide the perfect fit.