Features EPS Core Equipped with thick EPS inner core, it achieves a good shock absorption effect and ensures superb protection. And the liner is removable for washing, which is more convenient. Ventilation System Comes with 11 vents designed to ensure all-around ventilation to prevent your head from overheating and bring a cool experience. Adjustable Strap The helmet has an adjustable strap to prevent it from falling off during sports, making it more comfortable during sports. Adjustable Fit The helmet's adjustable buttons can be easily adjusted with one hand to make the helmet fit most head circumferences.