Crumbs
Product Images
Description
Watt Saving For Road Racing
There are lots of so-called aero socks out there. But the Castelli Fast Feet 4 Sock LTD has the development and testing to back up the claim. This sock can save 2 watts at 50 km/h. The newest version has an updated cuff fit for more comfort and aerodynamic gains.
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 Castelli created a jig that replicates the movement of the lower leg and then tested it on actual riders to verify the results.
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
- Fit: Race
- Weight: 48 g
B-Stock - This product has one or more B-Stock units available. These units can be purchased at a discount (see option select). B-Stock units were returned from other customers and may have missing or damaged packaging materials. These units are otherwise as new. The full manufacturer warranty applies. Click Here for more information.
Size Chart
| S/M | L/XL | XXL | ||||
| Shoe Size | 35-39 | 40-43 | 44-47 |
Specifications
White/Black/Red - S/M | Mfg PartNum: R4300727G001-2 |
White/Black/Red - L/XL | Mfg PartNum: R4300727G001-4 |
White/Black/Red - 2X-Large | Mfg PartNum: R4300727G001-6 |



















