OutdoorMaster Skateboard Bike Helmet for Adults &Youth - Multi-Sport Certified Impact Resistant with 2 Removable Liners & Ventilation for Scooter

" Technical Details Item dimensions L x W x H: 10 x 10.55 x 6.95 inches Item Package Dimensions L x W x H: 10.71 x 9.13 x 7.17 inches Features: High-strength ABS shell + dense EPS for durability. 12 ventilation holes for comfort. Adjustable system for different head sizes with one hand. Moisture-absorbing, washable chin pad. ABS shell EPS Foam POM Polyester Nylon About this item Double Adjustment: Well-attached long-lasting adjustment dial and skin-friendly adjustable chin strap maximize the best fit and comfortable wearing How to Measure A Proper Helmet: To find the right size bike helmet, start by measuring your head circumference, wrap a flexible tape measure around the largest portion of your head about one inch above your eyebrows. Or, wrap a string around your head, then measure the length of string with a yardstick. Size Large is recommended if your size is between 21.3-22.8 inch (54 cm-58 cm). Find Your Fit: Measure head circumference accurately with tape/string 1in (2.5cm) above eyebrows, around the widest part (snug, level). Compare to OUR chart. If 21.3-22.8in (54-58cm), Size L recommended (confirm chart). Always use our chart. Ages 5+. "