Castelli | Fast Feet 4 Sock Men's | Size Large/extra Large In Black

Jenson USA$65Buy

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From Jenson USA

Castellli Fast Feet 4 Sock Watts on Your Feet Most aero socks are tested statically, but a foot is never static on the bike. Castelli built a jig that replicates the actual movement of the lower leg, then verified the results on real riders. The Fast Feet 4 can save 2 watts at 50 km/h - a number that holds up under dynamic conditions, not just in a lab. The latest version adds an updated cuff fit for more comfort and aerodynamic gains. If you're racing on the road and can't run a shoecover, this sock is the next best thing.