DESIGN & TECHNOLOGY: Perfect for skiing, snowboarding and other snow sports activities Adult fit Aerocore(TM) construction with Koroyd(R) technology for improved temperature regulation MIPS(R) technology absorbs impact and protects by allowing only a small rotation of the outer shell relative to the liner AirEvac 2 ventilation technology pushes hot air out and cool, dry air through while keeping goggles clear of fog Regulator adjustable climate control with 14 vents for maximum airflow and climate control Custom fit with the adjustable dial fit system (DFS2) Includes Snapfit SL2 ear pads for comfort Certification: ASTM F 2040, CE EN 1077:2077 Class B Compatible with Outdoor Tech(TM) audio systems (audio system not included) SIZING: We recommend you try helmets on before buying. Make sure the helmet fits with a little room when the fit system is loose, and sits low enough to protect your child's forehead without hindering vision. Once you've got the right size, you can adjust the fit.