Please Note This Product Can't Be Returned. Breathable - 24 vents and a breathable lining keep you dry no matter how long you wear it. Comfortable - f eaturing a newly designed chin strap and padding, it is easy to use and ensures comfortable wear. Adjustable - an adjustment knob is provided to adjust the size according to head circumference. Convenient - made of special materials, it is very lightweight and easy to handle.