PLEASE VIEW ALTERNATE PICTURES WHICH GIVE EXACT SIZING DIMENSIONS FOR THE HELMET. Helmet is CPSC approved. The materials in this helmet allow it to be one of the lightest helmets on the market while still providing excellent durability and integrity. The multiple vents with inner air channels draw air through the helmet and over the brow for maximum cooling and support. Extra padding is included with the helmet; to ensure proper fit, you can mix and match the pad thickness to best suit your head shape.