Zipp: If perfection is the standard, then the 303 Firecrest wheelset delivers everything you could ask for, including a heritage forged in the Spring Classics. At the center of the 303 Firecrest Carbon Clincher is the 77/177 hubset, an innovation that results in improved stiffness, durability, simplicity and versatility.Zipp’s original 303 Tubular made history by becoming the first carbon wheelset to win cycling’s two most famous Cobbled Classics, Paris-Roubaix and the Tour of Flanders. Its wider rim provided extra durability, and improved aerodynamics. That wider rim also led to the development of our revolutionary Firecrest® platform, and now the revolution continues with the inclusion of the 77/177 hubset – best-in-class durability and improved bearing protection with no pre-load adjustment needed.- Optimized flange geometry and spoke hole attachment pattern with Sapim® CX Sprint spokes to optimize torsional and lateral stiffness and robustness.- Includes newly designed quick-release skewers with a wider more ergonomic handle to provide more leverage for opening and closing. When closed, lever contours neatly with the frame.- New robust hub platform with distinctive graphics.- For those looking for a wider gear range, or tackling especially extreme terrain, a XD driver body for 177 is sold separately and easily installed to allow for more cassette options including a 10-42. The hubset is designed to swap driver bodies without re-dishing wheel.Zipp’s Carbon Clincher technology preserves the aerodynamic advantages of the 303 Firecrest’s tubular brother, while adding the convenience of a clincher tire. And at just 1,645g, it’s light enough to climb up the steepest gradients with ease as a go-to all-around wheelset.The Firecrest shaping optimizes the aerodynamic profile of both the front half and the back half of the wheel. In addition, Firecrest moves the center of pressure of the wheel backwards, giving the 45 mm-deep rim the crosswind stability a box-section rim. At the same time, the 26.4 mm-wide brake track (at center) allows the clincher tire to take on a wider, more stable shape without compromising rolling resistance. It’s faster, simpler, and more stable.The new wheels retain all the small details that make Zipp wheels what they are. Exposed spoke nipples sit in the aerodynamic shadow of the rims, keeping serviceability simple without compromising speed. And our signature ABLC™ rim dimples squeeze every last second of performance possible.Available in two decal options, the stealthy Matte Black or the distinctive Matte White decals. Each 303 Firecrest Carbon Clincher wheel comes with Tangente Platinum Pro Evo brake pads, Zipp Integrated Valve Extender with valve-core wrench, rim tape and quick release.Product note:The wide profile of the 303 Firecrest is crucial to Zipp’s revolutionary Firecrest technology used to create wheels with superior aerodynamics as well as improved stability and handling.The rear 303 Firecrest, however, may present some fitment issues for a small number of road and triathlon frames. The clearance between the chainstay and the rim may not be adequate to avoid contact between each other when ridden under load.We urge customers who plan on riding the 303 Firecrest to test the wheel within the frame in which they intend to ride, under normal riding and road conditions, before purchasing. Clearance within individual frames of the same size, from the same manufacturer, may vary. That is why it is imperative that you test the wheel in your frame, or in the frame that you are considering purchasing.SPECSWeight - 900gHub Used - 177Rim Depth - 45mmBrake Track Width (center) - 26.40mmMax Width - 28.50mmClincher Bead Width - 17.25mmSpokes - Sapim CX-SprintSpoke Count - 24Spoke Pattern Non-Drive - 2 crossSpoke Pattern Drive - 2 crossSpoke Length Drive - 270mmSpoke Length Non-Drive - 272mmMax Tire Pressure - 125psiMax Tire Pressure - 8.62 bars11-speed compatible hub - YesTrack Adaptable - NoDimpled Surface - YesNipples - SapimExternal Nipples - Yes