If you have to cover your dome, and let’s face it, you should, then the 9MM by HIGHWAY 21 is a great way to do just that. Classic helmet design combined with premium material for a helmet that will protect your head, neck, and keep Johnny Law at bay. Durable lightweight ABS shell. EPS (Expanded polystyrene) interior. Diamond stitched Coolmax® liner. Washable and replaceable interior. Dual D-ring chinstrap. Protective helmet bag. D.O.T. approved.