Built on the foundation laid by firecrest offering unrivalled crosswind stability and the most aerodynamically efficient rim design on the market the 303 nsw takes it all to the next level like its siblings 404 nsw and 808 nsw our top engineers in the nest advanced development lab incorporated improved aerodynamics industry leading braking performance and reduced rolling friction to produce the lightest highest performance 303 wheelset zipp has ever made light enough to fly up climbs