Our kids bike helmet features a one-piece plastic impact-resistant shell and high-density EPS shock-absorbing cushioning to keep your child safe during any activity. Features: Switch between half and full helmet with ease using buttons on the sides for versatile conservation that meets your child's needs. 4 breathable vents and aerodynamic design provide cool airflow and reduce sweating while riding Come with a lightweight design that won't burden your child's head. Great for a wide range of activities, including riding, skateboarding, roller skating, inline skating, scootering, longboarding, and more. The head circumference adjuster ensures a secure and comfortable fit for your child's head, giving you peace of mind. Specifications: Material: Plastic Color: Red/ orange/ white/ green/ blue/ purple (optional) Head Circumference: 52 - 56cm / 20.5 - 22.0in (use 12mm liner); 54 - 58cm / 21.2 - 22.8in (use 8mm liner) Size: 32*18*18cm  / 12.6*7.1*7.1in Package size: 32*20*20 / 12.6*7.9*7.9in Package weight: 482g / 17oz Package list: 1 * Cycle Helmet