All Season Compatibility & Dual Certified for Snow & Bike - you can quickly and easily convert our Multi-Sport Helmets with BERN's Universal Summer Liner to bike/skate for year round usage. Sold Separately. Lightweight and Ventilated: Thin Shell w/ Ribtech construction, ventilated channels regulate your temperature while saving weight. Rotational Impact Protection, 14 Vents & 470g avg. weight Adjustable Fit: Feel snug and secure with our Compass Fit system, letting you dial into the perfect fit. Follow head measurement instructions for ideal sizing. Small: 52-55cm, Medium: 55-59cm, Large: 59-62cm. VISIBILITY: Quickmount Asteroid light compatible for enhanced visibility (sold separately) The Hendrix is the latest evolution of BERN's signature brim styling but formulated with premium, Hand Wrapped Carbon & ultralight RibTec EPS foam construction. Extremely durable, low profile, negligible weight & well equipped for all day comfort. Next level & timeless quality with over-the-top paint finishes that will never go out of style. Includes full Snowsports & Summer Bike/Skate Conversion Kit.