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Castelli Mens Unlimited 18 Sock Defender Green
Defender Green
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Castelli Men's Unlimited 18 Sock


Pricing and Order Section

Mfg PartNum:
Save 5%, 10%, or 15% more with purchase of 2, 3, or 4+ closeout items.
SALE: $9.99 pr.
MSRP: $19.99
That's 50% off
In Stock
Ships Free!
This color/size is not eligible for VIP points
Price matches are is not eligible for VIP points


Keep It Fresh

Castelli's Unlimited 18 Sock is a classic, mid-cuff cycling sock featuring a midfoot support band, reinforced heel and toe sections and antimicrobial Q Skin fabric to keep things fresh.


  • Q Skin yarns with antimicrobial silver ions to reduce odor
  • Pique ankle knit
  • Reinforced heel and toe
  • Midfoot support band
  • Available in a variety of colorways
  • Sizes: S/M-2XL

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.

Size Chart

Shoe Size


Cuff Height: Crew 

Fabric Type: Synthetic 

Defender Green - S/M

Mfg PartNum: R4522037346-2 

Defender Green - L/XL

Mfg PartNum: R4522037346-4 

Defender Green - 2X-Large

Mfg PartNum: R4522037346-6 


Ordered by Most Relevant First
5 stars
4 stars
3 stars
2 stars
1 stars
Reviewed 10/6/2022
by Andy
Portland, OR
Overall Rating
Comfortable but fragile

On sale, so I gave them a go. While the soles are sturdy and have held up nicely, the same cannot be said for the leg, which began fraying on me almost immediately. Giving them a 3/5 since they're still functional even though their appearance is kinda shot.

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Reviewed 8/19/2022
by Anonymous
Competitive Racer
Bend, OR
Overall Rating
0 of 1 customers found this review helpful.
Excellent fit and look.

I like the fit and I like the look. I have dozens of socks, and my faves are Castelli.

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