Zipp's 303 Firecrest Tubeless Disc-brake wheelset is designed for the real world a world of imperfect conditions, road surfaces, and elements where the bottom line is simple. Efficiency = speed. It's faster, lighter, and more capable over varied terrain whether the surface is pavement in all its conditions or no pavement at all. Deeply rooted in Zipp's drive to conquer the Spring Classics, the new 303 Firecrest is remade with a purpose-made approach for the demands of modern road bikes. When it comes to going fast on a bicycle, efficiency means reduced: Wind resistance, rolling resistance, rider fatigue, weight. The 303 Firecrest Tubeless Disc-brake was designed using real-world direct measurements (vs. primarily wind tunnel or computer simulation). The results were huge. Its rim is slightly more bulbous in design than its predecessor, with a 30mm outside width, a 25mm internal width, and a 40mm rim depth. The profile provides low drag and an improved transition between rim and tire, boosting aero efficiency on the road. The wide rim stance also features less tire deflection for reduced rolling resistance. The combination of the wider tire, increased tire volume, and lower tire pressure helps to reduce rider fatigue by smoothing out the ride over imperfect pavement and road conditions the tire and wheel system absorbs the shaking, not the rider. At the center of the 303 Firecrest Tubeless Disc brake is a versatile and durable new hubset, the German-engineered ZR1 DB. This hubset features 66 points of engagement for quicker response. The 303 Firecrest Tubeless Disc-brake wheelset is for dedicated cyclists who aspire to the latest in technology. Its competitorsÉ in races, against peers, or simply conquering personal limits. This is about becoming faster and matching your motivation to the most advanced technology.