The KRONOS Helmet makes the pinnacle of professional aerodynamic headwear available to cyclists in the U.S. It is the same TT helmet design and technology used by the Caisse d’Epargne/Illes Balears ProTour team. There is no other helmet available to consumers in the US with the technology and design of the Kronos that also complies with CPSC safety standards. Take your time-trialing and triathlons to the next level. Two slice-vents in the front funnel airflow and ventilation while maintaining the maximum aerodynamic integrity of the outer shell. The airflow is directed through the helmet with internal venting that is channeled to release directly out of an opening at the end of the tail piece of the helmet; an opening that is covered with a fine metal mesh finish. The retention system is Spiuk’s innovative COMPACTFIX technology allowing for millimetric precision in adjusting the tension. The Kronos also features a padded chinstrap and one-piece internal padding (both removable/washable). Weight 390 grams. Size: One size: M/L, fits 53-61cm (20.87-24.02") Team Cyclist is an authorized Spiuk dealer and will honor all manufacturer warranties.