The 177 rear hub was engineered to replace the 188. This complete re-design optimizes the strength and stiffness of the machined aluminum body and offset flanges, allowing for greater tension with the 24 straight-pull Sapim CX-Sprint steel spokes and standard Sapim external nipples. The same pre-adjusted bearing system you have the front is used for the rear hub, as is the lightweight oversized axle. The rear 177 hub is also more user friendly then the 188 when swapping out freehubs, or changing to a SRAM XD driver. There is no need to re-dish the wheel for such changes. Whatever freehub type you use, engagement is smooth, immediate and confident.

The Zipp 303 Firecrest Carbon Clincher rim has a wide stance that improves overall feel, handling and ride quality. It has a wider 28.50mm max rim width, with a 17.25mm internal clincher bead width. Firecrest rims have a near-constant width from brake track to spoke bed to improve aerodynamics and better control airflow. Zipp used Computational Fluid Dynamics software analysis to maximize the aerodynamics of the rim and dimpled ABLC surface while minimizing wind-produced torque, resulting in a rim design that is faster and better handling. The airflow is managed over the rim and passes more cleanly over the tire, which has less of a bulb-like shape than if the rim was narrower. The aerodynamics exceed that of the exceptionally fast previous generation 404 rim, yet is much more stable on any surface, and in heavy wind, with substantially improved braking. The brake track tapers to 26.40mm at the center, to ensure compatibility with most road braking systems. The braking surface features the molded in-groove technology that ensures excellent stopping power in wet, dry, or hot conditions. Optimal performance is achieved with the supplied Zipp Tangente Platinum Pro Evo brake pads. The Silicon Carbide particles employed in brake track resin add extreme hardness, making the track impervious to incidental damage. This combination of tech is called Showstopper, and the results are impressive and effective.

If you ride crits, road races, stage races, hill climbs, etc., and you can only have one wheelset, it has to be the 303. The carbon clincher technology means the convenience of clincher tires is raceworthy. Everyone would love tubulars as well, but you have to put your money and time where you get the best return. You can race and train on the same wheels, which leads to a comfort level that makes you a better rider. The rear 177 wheel weighs only 900 grams, the front comes in at 725g and the set rides even faster than expected. All of those qualities are also the reason why the 303 Firecrest Carbon Clincher 77/177 is favorite for serious riders who don't race. Every rider can enjoy the joy of riding pro-level wheels with incredible engineering and execution, from the master's of speed, Zipp.