Cycling Bicycle Adult Bike Handsome Carbon Helmet with Visor White Crashworthiness, not brittle to withstand the high intensity, strong foam density. Use ONE STEP technical material, EPS increases impact resistance of composite materials. Ultra-light, wind tunnel, duct design, effectively reduce wind resistance. High-quality foam layer, the adjustment within the twist, you can adjust the size of head circumference. Suitale for people with head circumference 54-65cm and the head-width below 16cm.