Giro Synthe MIPS Helmet The Giro Synthe is a true blend of all the features a modern rider wants out of a high performance road racing helmet. It delivers remarkable cooling power at a minimal weight along with a supreme fit and streamlined aerodynamic efficiency. Giro took the Synthe into the wind tunnel for extensive testing in order to bring to a level of aerodynamic efficiency that rivals some of the fastest time trial helmets on the market. It delivers on the aero front while still providing a comfortable fit and ventilation. The Roc Loc Air fit system has micro adjustment allowing for both tension and fore-aft fitting with just one hand. Cooling and ventilation power is increased by a massive number of ports along with internal channeling. You can have your cake and eat it too with the Synthe. Keep all the comfort without throwing out aerodynamics. Synthe MIPS If you've ever worn a Giro helmet you very well know that all Giro helmets are designed and built to reduce as much impact energy as possible in order to meet and exceed stern safety certifications. Building upon these industry leading designs and safety levels, this model of the Synthe employs MIPS technology to also reduce rotation forces. To accomplish this, MIPS technology mimics nature's own method of reducing forces transferred to the brain in the event of a crash. When subjected to an oblique impact, a membrane between the brain the skull allows the brain to slide along the inner surface of the skull, which ultimately reduces the forces transferred to the brain. MIPS helmets use a low friction layer between the shell and liner to mimic this process, which significantly reducing the forces transferred to the brain. Giro Synthe MIPS Helmet Features: Weight: 270 Grams (CPSC Medium) MIPS technology Featherweight Webbing with Slimeline buckle Roll Cage internal reinforcement Ponytail compatible ROC Loc Air 19 Vents, Internal Channeling Wind Tunnel-Aided Design for Aero Efficiency Road integrated Aero Mesh Panel Eyewear Docking Ports Giro Helmets (Superfit) HELMET SIZE CHART Size Small Medium Large Head Diameter (in) 20 - 21 3/4 21 3/4 - 23 1/4 23 1/4 - 25 Head Diameter(cm) 51-55 55-59 59-63 | Giro Synthe Mips Helmet Men's Size Small in Black