• Zox shield rapid change ratchet system. REAL CARBON FIBER SHELL - VERY BEAUTIFUL. • Carbon: safe and lightweight. ADULT SMALL - 55-56cm - 6 7/8-7 HAT SIZE - 21 1/2" TO 22". COST - FREE. • Injected visor anti-scratch shield exterior, anti-fog interior with curved, tapered edges & UV protection.