ProRider BMX Bike & Skate Helmets, Includes Bonus "Number 1 in Service" Logo Reflector Sticker, (Black, Small/Medium) Classic BMX Multi-Sports Helmet with Hard Outer Shell for Added Protection. Complies with CPSC Standards for Helmet Safety. Includes Padded Inserts to help adjust fit. Ventilation Channels for Cooling Comfort, Durable Polyester Straps with Quick-Release Buckle. SIZE CHART: Measure head circumference by wrapping a measuring tape around your head starting about an inch above your eyebrows and encircling the widest part your head. * X-Small: 20" - 21.25" (typically fits ages 3-6 years) * Small/Medium: 21.5" - 22.5" (typically fits ages 6-10 years) * Large/X-large: 22.75" - 24.5" (typically fits adolescents & adults) Be Protected While Riding Your Skateboard, Bike, Scooter, Roller Skates, Or Any Bike Sports. Satisfaction guaranteed, Choose from Different colors and sizes, Strong Quality, Comfortable Fit, Easy To Adjust, STAY SAFE!!!