Triple Eight Gotham Dual Certified MIPS Skateboard and Bike HelmetSize XS/S fits 18.9 a 21.3 in (48a 54 cm)S/M fits 21.7 a 22.8 in (55 a 58 cm)L/XL 23.2 a 24 in (59 a 61 cm)Manufacturer#8217;s 180-day warrantyTriple Eight Gotham Dual Certified MIPS Skateboard and Bike Helmet is the perfect blend of comfort. safety. and good looks. Dual-certified for both bike and skate. it has patented Multi-directional Impact Protection System (MIPS) technology that reduces rotational forces during impact. The innovative Conehead EPS liner offers additional protection with collapsing cones that act like a crumple zone to absorb the energy from a crash and spread the force sideways within the helmet liner. An ABS shell. with an urban profile and subtle brim. features Triple Eight logo vents for maximum airflow. #8211; Urban-style helmet with Multi-directional Impact Protection System (MIPS) technology that reduces rotational forces during impact #8211; Vented ABS shell with subtle brim. and lightweight Conehead EPS liner offers excellent airflow and maximum protection; ideal for biking. skateboarding. rollerblading. BMX. derby. and commuting #8211; Complies with U.S. CPSC Safety Standard for Bicycle Helmets for Persons Age 5 and Older and ASTM F-1492 Skate safety standards #8211; Includes two sets of removable. washable. terrycloth Sweatsaver Fit Pads. adjustable dial system. and chin strap with side release buckle for custom fit #8211; Size XS/S fits 18.9 21.3 in (48 54 cm) #8211; S/M fits 21.7 22.8 in (55 58 cm) #8211; L/XL 23.2 24 in (59 61 cm) #8211; Manufacturer#8217;s 180-day warrantyAssembled Product Dimensions (L x W x H): 11.00 x 9.00 x 7.00 Inches