With the Star Pro Helmet's wind-tunnel proven ability to gain . 9 meters every 300 meters over its closest competitor, Bell obviously doesn't have many options for improving it. In fact, it may only have one: adding a wind-shielding visor. By adding the magnetic, tinted Zeiss Shield to the Pro Star's refined, aerodynamic body and elements, Bell's engineers have made what may be the fastest cycling helmet on the planet. The Star Pro's Active Aero, which involves a switch and a slider, is the helmet's other aerodynamic-boosting feature. Sliding it open makes for more ventilation; sliding it shut blocks off the drag-creating vents at the helmet's front, presenting a unified front to the wind to take maximum advantage of the Star Pro's aerodynamic shaping. The Star Pro may be the only cycling helmet that literally has its own wind tunnel, as the Bell engineers built one for it to dial in the shape as much as possible. Even the straps are aerodynamic, incorporating Bell's new Cinch system to keep everything flat and unobtrusive while the FloatFit adjustment options ensure security. The Overbrow Ventilation design helps strike a balance between ventilation and aerodynamics courtesy of airflow channels running through the Star Pro's under belly. The brow provides a gap between helmet and forehead, which funnels air into the channels, which let it move unimpeded over your head and out the rear exhaust ports for efficient cooling. For climbs, you'll definitely want to supplement this with the Active Aero vents open, but it does a reasonable job keeping you cool with the vents closed when you're flying under the red kite with only a matter of seconds on the bunch. A helmet's aerodynamics and ventilation are nice, but it's important to bear in mind the reason why we're even discussing them. A helmet is protection first, aerodynamic second, and cool-looking third. (We do admit to sometimes inverting the second and third criteria. Happily, the Star Pro doesn't disappoint, ...