Castelli Fast Feet 3 Sock: Optimal Aerodynamics, Maximum Performance

In the world of performance cycling , every watt, every second, every detail counts. The Castelli Fast Feet 3 Sock was developed with advanced aerodynamic insights and intensive testing to give riders a measurable advantage at high speeds.

Developed for Speed

Many so-called aero socks promise speed, but the Fast Feet 3 Sock has the scientific testing to prove it. Castelli developed a unique test setup that simulates the actual movement of the foot , making this sock not only faster in theory, but also in practice.

• Aerodynamically tested on real riders and with a moving foot
• Saves up to 2 watts at 50 km/h for a measurable speed advantage
• Specially designed grooves in the Lycra® shaft to optimize airflow

Comfort Without Compromises

An aero sock should not only be fast, but also comfortable enough for long rides and races. The foot part is based on the Castelli Rosso Corsa Sock , which is known for its superior fit and breathability .

• Soft and breathable footbed for optimum comfort in the shoe
• Elastic polyurethane grip strip on top prevents slipping
• Lightweight materials for ventilation and dry comfort in warm conditions

Why Choose the Castelli Fast Feet 3 Sock?

The Fast Feet 3 Sock is an essential addition to the kit of any performance-oriented cyclist seeking measurable speed and ultimate comfort .

• Aerodynamically tested and proven advantage in the wind tunnel and on the road
• Optimized for warm conditions thanks to lightweight and breathable materials
• Perfect fit without sagging for maximum efficiency and comfort.
• Based on the renowned Rosso Corsa Sock for unparalleled wearing comfort