The reigning king of full-face helmets, the D4 range expands with a Polyacrylite model packing the same safety and comfort features as the premium carbon and composite models into a price-conscious shell. Details make the D4 the most coveted full-face in mountain biking, including Mips® C2 brain protection, an air intake system for ventilation, and an unmatched anatomical fit. This helmet is designed and intended exclusively for use by bicycling activities, including mountain biking and off-road cycling.