The Zipp 303 S disc brake wheelset offers modern road and gravel bike riders the versatility and speed they need to reach their top speeds.The wheelset maintains its ideal rim height of 45 mm and features an inner width of 23 mm.The 303 S are one of the lightest Zipp wheels optimized with a 28 mm tire for highest aero performance, but can also be ridden with gravel tires up to 50 mm wide. The overall 27mm wide rim, which is also tubeless capable, optimizes the tire shape to allow for lower tire pressure. This reduces rolling resistance and allows for a savings of 10 watts over a comparable high-end wheelset in the total power required to ride 40 km/h on a flat road with a 28 mm tire. Plus, the Zipp 303 S come in a totally optic. Construction: rear. Intended use: road bike. Axle system: HR 12x142 mm mm. Maximum tire pressure 73 psi. Maximum rider weight 113 kg. Axle standard: thru axle rear hub. Rear axle diameter: 12 mm. Installation width: 142 mm. Sprocket type: 10/11-speed SRAM/Shimano. Type: 176D. Spokes count: 24. Features: sealed rims. Construction: hollow chamber. Braking system: disc brake. Tubeless compatible. Width: 27 mm. Tread height: medium (30 - 50mm). Material: Carbon. Size (in inches): 28 inch. Mouth width: 23 mm. Height: 34. tyre type: clincher. Included in delivery: Spacer for 10-speed cassettes, Centerlock locking ring, Tubeless valve, valve wrench, Tubeless rim tape Spokes. Construction: Spokes: CX-Sprint / nipples: Sapim Secure-Loc. Lacing: 2 way crossed Rear wheel. Designed for brake type: disc brake. Center Lock. Weight: 819 g.