Description: Quality Material: The Skateboard helmet is made of a quality PC shell with an EPS layer inside, providing strong impact resistance and effective protection against collisions.Portable Design: Weighing only 293g, this Cycling helmet is portable enough to be worn comfortably for extended periods of time, making it great for city commuting, leisure trips, electric bikes, bicycles and more.Adjustable Size: With a head circumference adjustment system that allows for 360 single hand operation, this helmet (57 cm-61cm) can fit most adults comfortably.Comfortable & Easy to Clean: The Roller skating helmet features a removable and washable inner lining design that provides shock absorption protection and a comfortable wearing experience. It also comes with two types of visor linings for replacement.Convenient Features: The bike helment has adjustable buckle allows you to easily change the length as desired while the EPS foam material used in the inner shell enhances comfort and shock absorption. Specification: Material: PC EPS Size Chart: Applicable Head Circumference: 57 cm - 61 cm / 22.44 inch - 24.02 inch Package Includes: 1 Roller skating helmet Note: Please allow slightly errors 1-2cm differences due to manual measurement.