Age range (description)Kid; toddler; teen Sizec small: 18.9"-21.26" / 48cm-54cm Outer materialAcrylonitrile Butadiene Styrene About this product What You Will Receive- Made of ABS EPS, light weight f kid's cozy wearing, provides me safety. ABS shell resists impact high density EPS inner shell soft liner. Such Designed f youth bike helmet with protective gear set f girls boys in black/blue/pink/purple, comes with 7 pieces set including 1 x Helmet, 2 x Elbow Pads, 2 x Knee Pads, 2 x Wrist Pads, please check the items clearly when you received the package. Adjustable Multispt Kids Helmet- Befe you use the helmet, please untie the buttons that connect the straps on both sides of the helmet. Depending on the size of your head, rotate the red adjustable knob on the back of the helmet attach the button in the middle of the strap. Helmet with Protective Gear SetHelmet head circumference: 48-54 cm/18.9"-21.3", come with an adjustable helmet turning knob adjustable straps which makes it flexible to fit perfectly f ages 3-8 boys girls. Multiple adjustable elastic straps velcro closures fit f various knee/Wrist/Elbow circumference. Use f:- This helmet could be used f many occasions to keep your kids safe, such as bicycling, roller skating, skateboard accessroies, scooter, hip-hop, rafting, head turning, mountaineering, river rafting, rafting, cave rescue, expansion, downhill, etc. Gift Ideas- Great holiday gifts f your boys girls! It is a good choice as Children's Day gift, Christmas gift, birthday gift other festival gift. It is packaged in a beautiful box the child will be overjoyed when he/she receive your present!