【Adjustable Size】This road bike helmet has a size adjustment dial on the back of the head, allowing you to adjust the size according to your head circumference. It provides a comfortable fit and plenty of safety. It also features a one-touch chin strap that can be easily put on and taken off with one hand, making it very convenient. 25-24 #See's Product List Bicycle Helmet for Adults, Ultra-Lightweight, High Rigidity, Impact Resistant, Bicycle Helmet, Streamlined Design, CPSC/CE Safety Standard Certified, Road Bike, MTB, Commuting, School, City Riding, Cycle Helmet, 18 Ventilation Holes, Men's and Women's, Unisex, Adjustable Size 54-62CM M/L ✅ As stated in my profile, shipping is suspended on weekends and holidays due to personal circumstances. Shipping will resume on Mondays or later. Thank you for your understanding. Price negotiations are also welcome⭐︎ ＊Instant purchase is welcome, silent purchase at midnight is OK◎ ＊First come, first served for single items ＊Bulk purchases are welcome, please feel free to comment ＊Free shipping! ・Please understand that items are stored at home and shipped in simple packaging. ・Please check the actual photos for the condition of the product♪ ※To keep prices as low as possible, we may ship items without their boxes due to shipping costs.