Feature: Warm and Cosy military hat - All seams are neat and flat Ultimate Thermal Retention - made of windproof fleece with membrane for EXTREME cold and STORM wind weather Sizing for Perfect Fit -24*23cm/9.45*9.06in Suitable for head circumference:53-60cm/20.87-23.62in Low Profile Design - wear it under hood or as helmet liner. Perfect for police army swat teams usmc navy or any military units members Hypoallergenic - is less itchy and irritating than regular watchcap