Product details:

Thermoplastic Alloy Shell: Lightweight, superior fit and comfort using advanced CAD technology. Aerodynamic Visor: Low-profile design. Two Forehead Vents: Delivers cooling air. Nylex Interior: Plush, moisture-wicking fabric. Removable 淶ip-outNeck Curtain: Easy to remove. Optional Face Shield Sold Separately. DOT approved. For proper fit and size measure the circumference of your head 1 above your eyebrows and around the largest portion of the back of your head.