Zipp’s 303 S Tubeless Disc Brake wheelset provides today’s cyclists the versatility they demand with the speed they crave. Expanding greatly on its heritage of conquering the Spring Classics, this 303 wheelset maintains its ideal-for-every-terrain 45mm rim depth but adds a significantly wider internal width to provide greater performance and ride quality in almost every measurable way. Road bikes are more versatile than ever, no matter the road surface, but just as fast as before. The 303 S offers an entirely new rim profile and design to optimize rider performance on this new breed of bike. This wheelset is tubeless for disc-brake bikes, allowing the ability to run wide tires at lower pressures for race-ready speed on or off the pavement. The 303 S is among our lightest wheelsets, optimized for top aero performance with a 28mm tire but capable of handling gravel tires up to 50mm wide. The 303 S borrows design concepts from the higher-level 303 Firecrest Tubeless Disc-brake wheelset to gain speed through increased efficiency. That is achieved by creating a wheel with reduced: Wind resistance, rolling resistance, rider fatigue, and weight. The key innovation is in the 303 S Series’ rim design. Its 45mm rim depth is the same as its predecessor, the 302 Disc brake. But its rim width is 2mm wider, at 27mm, and its tire bed is a full 7mm wider, at 23mm. That rim platform is designed to be the fastest with a 28mm tire. The wide rim optimizes tire profile to allow lower tire pressure. That helps to reduce rolling resistance and provides a more compliant ride. The result of all this is a 10 percent watt savings vs. a top peer wheel in total power required to ride 40kph on a smooth flat road with a 28mm tire, according to internal Zipp testing. This groundbreaking wheelset also features all-new cosmetics, setting the rider apart from the pack, and comes at an attractive price. Model ID WH-303-STLD-A1 Features Zipp graphics and cosmetic identity that scream speed Fastest with 28mm, fits wide gravel tires as well 76 / 176 DB hubs with Center locking interface XDR and HG driver body option available Wide rims optimize tire profile to allow lower tire pressure, especially with tubeless. The result is a larger contact patch for increase grip for confident cornering, descending, and handling in wet conditions. Lower tire pressures and larger volume provides a compliant ride with fewer vibrations. Significant watt savings when running larger tires at lower pressure. Wide hookless rims create a seamless transition to the tire, reducing drag.