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Castelli Womens Alpha 15 Sock
Castelli Womens Alpha 15 Sock
Castelli Womens Alpha 15 Sock
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Castelli Womens Alpha 15 Sock
Castelli Womens Alpha 15 Sock
Castelli Womens Alpha 15 Sock

Castelli Women's Alpha 15 Sock

Mfg PartNum:
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Ride Like an Alpha

It doesn't matter whether you're racing, trail riding, or just cruising to the local coffee shop to get a latte, you need to have a strong sock game. Castelli Women's Alpha 15 Socks are designed to be more breathable and wick moisture better than the regular socks you've grown tired of.

Constructed with a mixture of PrimaLoft® and merino wool, these socks provide the moisture management you need after a long ride. A compressive band at the arch keeps your foot supported, while a nylon heel and toe deliver on the durability you need to reduce holes. The 15cm cuff provides extra coverage and warmth while you log in the miles.

Need an extra boost while riding in low-light conditions? The Alpha 15 features a reflective stripe on the back for increased visibility. Make the most of your rides with the cold weather sock maximized for warmth.


  • PrimaLoft® and merino wool blend keeps feet warm and dry
  • Arch-support band keeps foot supported with compression
  • Nylon heel and toe delivers durability for many miles
  • Reflective stripe on back enhances your visibility
  • Tall 15cm height for comfort and support while riding

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.

Discount Codes are not applicable to Closeouts.

This product is NOT Eligible for VIP Points.


Cuff Height: Crew 

Fabric Type: Synthetic 

Black/Dark Gray - S/M

Mfg PartNum: R4521558010-2 

Black/Dark Gray - L/XL

Mfg PartNum: R4521558010-4 

Dark Steel Blue/Soft Pink - S/M

Mfg PartNum: R4521558070-2 

Dark Steel Blue/Soft Pink - L/XL

Mfg PartNum: R4521558070-4 

Teal Blue/Fiery Red - S/M

Mfg PartNum: R4521558324-2 

Teal Blue/Fiery Red - L/XL

Mfg PartNum: R4521558324-4 

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*Orders received before 3:00PM Pacific time are shipped the same day (Mon-Fri). Orders over $50
are shipped free (USA only, excluding AK and HI). Some exceptions apply. See Shipping for details. 81


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