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Item # CST2610

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Item # CST2610

Sock it to 'em.

The Castelli Free 9 Sock is to regular socks as space shuttles are to balsa-wood gliders—the basic design is similar, but everything that matters is totally different. The Free 9 is woven from Meryl Skinlife fibers, which are engineered to be antimicrobial, highly breathable, and moisture wicking, so your feet stay fresh, dry, and comfortable. A high-density woven band under the arch supports your foot and prevents slippage without adding any extra thickness, a flat toe seam prevents irritation, and an open mesh panel at the cuff increases airflow to provide unbeatable ventilation.

  • Meryl Skinlife fibers
  • High-density woven arch band
  • Flat toe seam
  • Open mesh cuff panel
  • Antimicrobial
  • Breathable and moisture wicking

Tech Specs

Material:
Meryl Skinlife
Recommended Use:
cycling
Manufacturer Warranty:
30 days

Size chart

Castelli

Socks

Castelli Socks
S/M L/XL XXL
US Men's shoe
size
4-7 8-10 11-14
US Women's shoe
size
5-7 8-10 11-12
How to Measure:
For best results, take measurements over your underwear.

Reviews & Community

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Castelli Free 9 Sock

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Here's what others have to say...

5 5

Great lightweight sock

  • Gender: Female
  • Familiarity: I've put it through the wringer

I am a women's 9 and I bought a L/XL, though I was weary of the size since a women's 9 is usually a men's 7. Originally this footbed on the sock was way too long, but now fits perfectly after one machine-wash on delicate (had only handwashed before). The band can be rather snug and the logo stretched if you have bigger legs but the sock won't fall down! Great fluoro color, no bunching, and very breathable.

5 5

Nice socks

  • Familiarity: I've put it through the wringer

These have been great so far this summer. I wear a 9-9.5 size shoe and ordered the L/XL size for these socks. I would go with the smaller size if I order more - the foot area of the sock is just a little too long for my preference (not the height of the sock, the foot area).

5 5

THE BEST!

Castelli Free 9's are my absolute favorite summer cycling socks. These socks are amazingly well ventilated on the top of the foot and all the way around to the top of the cuff. You can use these socks on even the hottest Summer days.

And 9 cm is the -perfect- height. You see this cuff height the most in the pro peloton. It covers the ankle and the achilles tendon, but does not extend onto the calf muscle.

In sum, these Casteli socks provide great quality, fit, ventilation, and they stay up. Lastly, they look -awesome- if you wear white cycling shoes!

Sizing: I'm a 45.5 euro in Sidi (10.5/11.0 USA). I bought both the L/XL and the XXL. The XXL fit better. If your foot is 46 euro or larger, definitely go with the XXL. Made in Italy.

5 5

These socks though!!!

  • Familiarity: I've put it through the wringer
  • Fit: True to size

Yeah, just buy a pair or two, or 5 like I did.
Fit great, look great ride well.