1. Product name: Bicycle one-piece molding helmet 2. Material: PC + EPS external IN-MOLD (one-piece molding) impact-resistant PC and internal EPS ensemble-shaped one-piece molding helmet with impact absorption skills, extension, impact-sharing 3. Head circumference: 54-61CM (adjustable) 4. Product weight: 210G 5. Age: adult bicycle helmet 6. Color: 17 kinds of optional 7. Helmet outer size: about 28 * width 21 * height 15CM Head circumference: even size adjustable 8. Adjuster system: lightweight fit, with adjuster knob, easy to adjust the size of the head circumference head circumference 9. Ventilation roar, 18 EPS molding vents 10. Inner cushion: 5MM silver gray inner cushion Removable and washable inner cushion Inner cushion (cushion comfort pad) and head contact to increase comfort Removable and hand washable 11. Chin pad: comfort lined chin pad to maintain a good fit Please don't hesitate to contact us if you have any questions or concerns before or after your purchase. We are committed to your 100% satisfaction. If you want to exchange the items received, you must contact us within 3 days of the receipt of your order. And you should pay the additional shipping fees incurred and the items returned should be kept in their original status. Since your feedback is very important to our business`s development, we sincerely invite you to leave positive feedback for us if you are satisfied with our product and service. It`ll just take you 1 minute. Thank you!