Bell: BUILT TO LEADEvery watt counts. The Z20 Aero is built with that in mind, delivering uncompromising performance, innovation, fit and comfort. With its drag-defying shape, Progressive Layering, and Integrated MIPS, this helmet provides real-world performance for riders who want to lead.FEATURESIntegrated MIPS (Multi-Directional Impact Protection System) - MIPS is designed to reduce rotational forces that can result from certain impacts. By integrating the MIPS slip plane into the retention system, we are able to reduce complexity and weight for a compact, better ventilated helmet that fits more closely to the head.Progressive Layering: The process of engineering a helmet liner with variable EPS foam densities to better manage the transfer of energies after some impactsFusion In-Mold polycarbonate shell - A process pioneered by Bell bonds the helmet's outer shell to the EPS foam liner to create a sturdier helmet.Float Fit Race - A state-of-the-art lightweight fit system featuring seamless integration with MIPS, an easy-to-turn dial, wide-range vertical adjustment and padded width-adjustable cradlesOverbrow Ventilation features intake ports on the brow of the helmet to usher in cool air and push it through the air-channel matrix for full-head ventilation10 ventsAero-optimized shapeNo-Twist Tri-Glides: Quick-adjust fasteners that help keep straps flat and properly positionedX-Static padding: Quick-drying materials, woven with real silver fibers, inhibit growth of odor-causing bacteria and fungiCE EN1078 certifiedCONSTRUCTIONProgressive Layering: The process of engineering a helmet liner with variable EPS foam densities to better manage the transfer of energies after some impactsFusion In-Mold polycarbonate shell - A process pioneered by Bell bonds the helmet's outer shell to the EPS foam liner to create a sturdier helmet.FIT SYSTEMFloat Fit Race - A state-of-the-art lightweight fit system featuring seamless integration with MIPS, an easy-to-turn dial, wide-range vertical adjustment and padded width-adjustable cradlesNo-Twist Tri-Glides: Quick-adjust fasteners that help keep straps flat and properly positionedLightweight strapsVENTILATION10 ventsWEIGHT274 grams (size M)