Kids Helmets Children's Multi-Sport Safety Bike Helmets Cycling Skating Scooter for Girls/Boys Material:PC Injection Moulded shell +EPS Polystyrene /Foam, CE certificate Color:Blue,Head size: 48~52cm,Head Width: 16.5cm,Taking into account the child head circumference size difference,so this item is enough stock Fulfilled by Amazon,if you have size problem ,you can contact with Amazon customer service,a simple solution Unique design-the bright colors with cute,brave,and awesome dragon teeth design,can let your child full of courage and energe,develop love for nature,passion Well padded and very comfortable,4 hole ventilation system Perfect for many kind sports such as bicycle,Roller-Skating,scooter,Ties and adjusts easily