Key Specs & Design Features

1. Rim Profile & Material

   • Deep 58 mm rim depth, which gives a good aerodynamic advantage.

   • Full carbon clincher construction (not an alloy brake track version). 

   • Uses Zipp’s Firecrest rim shape, which is designed for better stability, especially in crosswinds. 

   • Dimples in the rim surface (ABLC – Aerodynamic Boundary Layer Control) to help with airflow. 

2. Braking / Brake Track

   • Alloy brake track (for rim-brake versions), so it's compatible with standard rim brake pads. (Note: your stopping power depends on the version — some Firecrest 404s are disc, but this one is rim brake.) 

   • Brake track width (at the center) is ~24.73 mm.

3. Hub & Spokes

   • Uses a Zipp 77 front hub (for older rim-brake 404s) in many configurations. 

   • Spoke count: 18 spokes, laced radially on the front.

   • Spokes are Sapim CX-Sprint, straight-pull.

4. Weight & Load

   • The front wheel weighs about 755 g (for 700c version

   • Zipp’s recommended maximum rider weight is 250 lb (≈113 kg) for this wheel.

5. Tire Compatibility & Pressure

   • Internal clincher bead width is ~16.25 mm. 

   • Max tire pressure quoted at 125 psi

6. Included Accessories

   • Comes with quick release, rim tape, Zipp integrated valve extender (with valve-core wrench), and brake pads (usually Tangente Platinum Pro Evo). 

7. Ride Feel & Performance

   • Because of the 58 mm profile, it’s a very balanced “all-round aero” wheel: aerodynamic in the flats and efficient on rolling terrain, but not as deep as super-deep aero wheels.

   • The Firecrest shape helps with crosswind stability, giving more predictable handling compared to some deeper, narrower rims.

   • The VCLC (Visco-Elastic Constrained Layer Control) system helps absorb road vibrations. In older 404 clincher models, Zipp claimed up to ~10% vibration reduction.

8. Durability & Use Cases

   • Suitable for a variety of riding: racing, triathlon, crits, long road rides.

   • Designed to be relatively robust for a carbon clincher, especially given the alloy braking surface and the structural carbon layup.

This specifications are from the information the brand releases and only apply to stock bicycles, build ups´ specifications will vary according to the components the buyer chooses.