Equipped with ventilated holes, the helmet is breathable. And the ultralight design and adjustable strap make it comfortable to wear. As the bicycle helmet is shock absorbing and impact resistant, it can protect your head from injury when you are riding on the road. Made of PVC and EPS material, it is durable and waterproof. The length of this bicycle helmet is 28cm, width is 21cm, and height is 15cm. The head circumference is from 58cm to 61cm. It is suitable for riding, cycling, skateboarding and so on. Item Name: Bicycle Helmet Material: PVC, EPS Features: Ultralight, Protective, Adjustable Circumference Size Details: One Size: 28cm x 21cm x 15cm/11.02" x 8.27" x 5.91" (Approx.) Head Circumference: 58cm-61cm/22.83"-24.02" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Bicycle Helmet