Two years in design and testing, the Shock Top® "Chill" Head Gear now answers singularly the biggest problem facing all headgear on the market today, overheating! Designed with "Venturi" air channeling more commonly used in cycling helmets, Shock Top® has created a headgear that will not only run cooler, but provide the maximum allowable protection as well. External and internal channeling to promote the airflow around the head. 4 large ear slots for improved hearing. Ergonomically designed face profile to allow maximum peripheral vision without reducing protective cover. 4 extremely adjustable sizes to fit the majority of head profiles.