Built with the same core design principles as the pro-level Z20, the Stratus combines lightweight aero efficiency with cutting-edge comfort technologies. The shape was refined for all-around road performance - ventilated for long climbs but still fast for the flats - and the integrated Float Fit system offers comfort and security with a streamlined fit and an oversized dial that''s easy to adjust with one hand. The Overbrow Ventilation system pulls cool air in through the front and pushes it through an air-channel matrix to reduce overheating. And thanks to the adjustable No-Twist Tri-Glides, the straps stay flat and properly positioned no matter how hard you''re hammering. This model also includes MIPS (Multi-Directional Impact Protection System) for added protection in certain types of impacts.