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Castelli Fast Feet 4 Sock

Castelli Fast Feet 4 Sock

Castelli Fast Feet 4 Sock

For road racing or when you can't wear a Fast Feet TT Shoecover, this sock saves watts.

PRODUCT FEATURES 

Castelli's Fast Feet project — for maximum aerodynamics

Foot portion based on Castelli Rosso Corsa Sock for in-shoe comfort

Polyurethane grip strip at top to keep sock in place

Leg portion constructed with engineered grooved Lycra® to help detach airflow

TECHNICAL FEATURES

Insulation 1/5

Waterproofness 1/5

Windproofness 1/5

Breathability 4/5

Lightness 4/5 

  • Weight:48 g
  • Temperature:10°C - 38°C / 50°F - 100°F
  • Fit:Race

 


FAST FEET 4 SOCK

There are lots of so-called aero socks out there. But the Castelli Fast Feet 4 Sock has the development and testing to back up the claim. The few socks that have been tested have probably been tested with a static, nonmoving test because it's easier. But a foot is always in motion, so we created a jig that replicates the movement of the lower leg. And we tested it on actual riders to verify the results. This sock can save 2 watts at 50 km/h. The newest version has an updated cuff fit for more comfort and aerodynamic gains.
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From $18.49

Original: $52.82

-65%
Castelli Fast Feet 4 Sock—

$52.82

$18.49

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Description

For road racing or when you can't wear a Fast Feet TT Shoecover, this sock saves watts.

PRODUCT FEATURES 

Castelli's Fast Feet project — for maximum aerodynamics

Foot portion based on Castelli Rosso Corsa Sock for in-shoe comfort

Polyurethane grip strip at top to keep sock in place

Leg portion constructed with engineered grooved Lycra® to help detach airflow

TECHNICAL FEATURES

Insulation 1/5

Waterproofness 1/5

Windproofness 1/5

Breathability 4/5

Lightness 4/5 

  • Weight:48 g
  • Temperature:10°C - 38°C / 50°F - 100°F
  • Fit:Race

 


FAST FEET 4 SOCK

There are lots of so-called aero socks out there. But the Castelli Fast Feet 4 Sock has the development and testing to back up the claim. The few socks that have been tested have probably been tested with a static, nonmoving test because it's easier. But a foot is always in motion, so we created a jig that replicates the movement of the lower leg. And we tested it on actual riders to verify the results. This sock can save 2 watts at 50 km/h. The newest version has an updated cuff fit for more comfort and aerodynamic gains.
Castelli Fast Feet 4 Sock | Rouleur Cycles