FEATURES: Compact design 18 wind tunnel vents with internal channeling keeps things cool even when the riding gets rowdy - Quick dry padding - Slimline webbing - Reflective accents CPSC Safety Standard for Bicycle Helmets for persons age 5 and older TECHNOLOGY: Equipped with MIPS ...FEATURES: Compact design 18 wind tunnel vents with internal channeling keeps things cool even when the riding gets rowdy - Quick dry padding - Slimline webbing - Reflective accents CPSC Safety Standard for Bicycle Helmets for persons age 5 and older TECHNOLOGY: Equipped with MIPS, the Multi-Directional Impact Protection System, so you not only stay cool but stay safe with extra protection and durability - Integrated MIPS reduces rotational forces while enhancing comfort and fit - Roc Loc Sport MIPS fit system offers a stable and custom fit SPECS: Universal Fit Adult Size: 21.2 in. - 24 in. / 54 cm - 61 cm.