Stilo's ST5 GT line of racing helmets are engineered for maximum flexibility to integrate into any racing environment. Featuring a taller eyeport to allow for use in both closed and open cockpit racers, the ST5 is constructed using two shell sizes - one for X-Small through Medium, and another for the larger sizes - allowing for weight savings without sacrificing fit. Side-mounted ports allow for the easy integration of intercoms, hydration systems, forced-air, or all 3!