Description: 【Premium Material】: This stylish kids bicycle helmet is made of premium PP foam and PC sheet material. It features an integrated lightweight design that provides great impact and shock protection, as well as cushioning. 【Comfortable Design】: The bike helmet for kids has a streamlined structure with ventilation holes and a breathable, comfortable lining that can be removed for easy cleaning. It keeps your head fresh and comfortable even when worn for extended periods. 【Adjustable Fit】: Equipped with thick padding, this children cycling helmet offers a comfortable and breathable fit suitable for most head circumferences (50cm-55cm/19.69inch-21.65inch). The inner width is 17cm/6.69inch, the inner length is 21cm/8.27inch, while the outer dimensions are 35cmx19cmx23cm/13.78inchx7.48inchx9.06inch. 【Aerodynamic Performance】: The road cycling helmet for kids is with lightweight, breathable, and comfortable design that can effectively reduce wind resistance to keep you cool and comfortable during your ride without causing fatigue. 【Versatile Use】: This kids helmet is widely suitable for balance bikes, skateboards, roller skates, road bikes or bicycles. Also a g great gift choice for boys and girls on birthdays, holidays, festivals, etc. Specification: Material: PP PC Size Chart: Size (50cm-55cm/19.69inch-21.65inch) Inner Length 21cm/8.27inch, Inner Width 17cm/6.69inch Outer Size 35cmx19cmx23cm/13.78inchx7.48inchx9.06inch Package Includes: 1 Kids Bike Helmet Note: Please allow slightly errors 1-2cm differences due to manual measurement.