From Split Second to Aero 6.0 The original Castelli aero jersey for road racing first saw light in 2006. It was known as the Split Second jersey. It was at a time when aerodynamics was only really considered important for time trials. Baggy cycling jerseys were the norm until that very first Castelli aero-focused jersey appeared. However, with every new version of the jersey, the aerodynamic advantages have proved to be worth far more than just a few split seconds. It’s now known as the Aero Race 6.0 Cycling Jersey - designed to take your velocity up another notch. Using CFD (Computational Flow Dynamics) to analyse wake flow, the Aero Race 6.0 will fit you even better when you're in an aggressive riding position while seam placement has been optimised to minimise drag. At speeds of between 30 and 55 km/h, the aerodynamic efficiency is optimised giving more speed without an increase of power output compared to a standard jersey. Same training. Same power. More speed. You could almost call it free speed. Cool and Fuelled Of course, riding fast, whether in training or racing, is going to generate heat. That, in turn, leads to sweat. However, the Aero Race 6.0 isn't just efficient through the air it's also efficient in dealing with moisture too. Quick wicking and with a 3D mesh back you'll be cooler and drier as you push hard on the pedals. To keep you up to speed and fully fuelled for your ride, the pockets are easily accessible when stuffed with gels and thanks to the drop tail design the jersey remains sleek even when they're loaded up. The Aero Race 6.0 Jersey is Castelli's most aerodynamically advanced design to date and yet it's also their best fitting too - Just ask their WorldTour professional riders. A remarkably comfortable high-performance cycling jersey whether it's your longest days in the saddle or a short and intense criterium race.