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The Synthe flawlessly combines ventilation with performance.
Weighing in at a mere 250 grams, the Synthe melds the qualities of two helmets in the Giro lineup—it features the aerodynamic features of the Air Attack aero road helmet and the lightness and ventilation of the company’s traditional training helmet, the Aeon. Although wind tunnel tests showed the Attack is still faster when the head is tucked, Giro claims the aerodynamics of the Synthe are on par with time-trial helmets in a traditional road or climbing position. It features the same internal locking system as the Attack, which pulls the helmet up and away from the head. For racing a triathlon, a true aero helmet is still the fastest bet, but for a high-performance training option with supreme ventilation, the Synthe is a welcome upgrade.