The Tardiz helmet is designed for Triathlon and like the Dr's phone box will help you move through space and timeThe Tardiz is a cross between a TT and a road helmetIt has the aerodynamics of a TT helmet but combined with the ventilation and comfort of a road helmetTardiz is the first helmet designed with the specific needs of multi-hour triathlon racing in mindAerodynamic performance without the risk of overheatingSix vents assure airflow over the riders head with an additional Aquavent, a ventilation port on the top surface of the helmet which allows the option of delivering water into the helmet to prevent overheatingSpecial perforated EVA padding and EVS channelling allows the water to filter down and around the headOptimal water and air flow over the head provides for maximum cooling and riding efficiencyDual Layer Aerodynamics, a front glossy surface and a back matt dimpled surface, provides the best possible airflow over and around the helmet surfaceAn optional Lazer Aeroshell available separately, covers the front ventilation holes and helps increase aerodynamics when installedThe Rollsys Retention System and Magic magnetic buckle, makes putting the Tardiz on easy, quick and comfortable for fast transition timesIncludes a drag reducing clear lensWeight: 400 g for a size mediumSize: Medium 55-59 cm, Large 58-61 cm