Zipp: The 303 Firecrest Tubular Disc-Brake Wheelset, Pro Proven In Cyclocross, Is Now Even Better & Lighter. At The Center Of The Wheelset Is Zipp's 77/177D Hubset, An Innovation That Results In enhanced Stiffness, Durability, Simplicity & Usability. The 77/177D Hubset Is The Perfect Compliment For The Leading Aerodynamics, Ride Quality, Stability & Rim Strength Of Zipp's Firecrest Rim Technology. That Means You Get The Unmatched Performance Of The 45 Mm-Deep 303 Firecrest Rim Proven With Victories Multiple Victories At Paris-Roubaix, The Tour Of Flanders & Pro Cyclocross Races. & When It's Time To Scrub Off Speed Or Stop, You Won't Have To Tense Up & Grab A Handful.' You Have The Consistency & Power Of Disc Brakes Precision Modulation & Stopping Power Is At Your Fingertips. On Top Of That, The Revised 303 Firecrest Tubular Disc-Brake Wheelset Is 35 Grams Lighter Than Its Predecessor. You're At The Helm Of A Serious Speed Weapon That Helps Speed Up & Smooth Out Even The Most Chaotic Courses. That's True Even When The Conditions & Terrain Get Crazy In Cyclocross Gravel Roads Steep Lonely Lanes Or Even Urban Assaults. Jeremy Powers (Rapha-Focus) & The Giant Factory Off-Road Team Raced Zipp 303 Firecrest Tubular Disc-Brake Wheels With New 77/177D Hubset To Great Success This Season, Including Power's 2015 U.s. National Championship Victory.