The New Rover Mountain Bike Helmet now with a Two Position Adjustable Visor. Using Smithís proven Aerocore Construction featuring Koroyd, the Roverís clean design target in on important zonal impact areas, offering better protection where & when it matters most. We combine this with our Air Evac ventilation & Vapour Fit adjustable fit system, creating the perfect balance of comfort & confidence for any ride. Koroyd provides superior impact absorption, design flexibility & ventilation when compared to materials used in traditional helmet construction such as EPS. By utilizing crumple-zone cylinders that crush uniformly on impact. Koroyd manages energy more efficiently with less volume than any other protection material on the market. Unlike traditional protection materials, Koroyd cylinders absorb & convert more kinetic energy, whilst increasing air flow & reducing overall weight. Not all helmets are equal.