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SmartWool PhD HyFi Knee Warmers

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  • Stretch-knit fabric blends fine merino wool with synthetic fabrics for warmth and wind resistance
  • Silicone grippers on inside and outside of top cuffs hold SmartWool PhD HyFi knee warmers in place
  • Reflective logo at bottom cuff
  • Please note: SmartWool recommends buying the same size knee warmer as your normal base layer, cycling short or tight size


  • SmartWool recommends buying the same size leg/knee warmer as your normal base layer, cycling short, or tight size
  • Small/Medium: fits most women
  • Large/X Large: fits most men


Item 835485


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SmartWool PhD HyFi Knee Warmers Specs
Best use
45% nylon/39% merino wool/16% elastane
Knee warmer
Sun-protective fabric
Warmer type

SmartWool PhD HyFi Knee Warmers

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Rated 5.0/5 based on 2 reviews
Rated 5out of5
by fromWarm and comfortable I had previously bought the SmartWool arm warmers and like them a lot. The knee/leg warmers are the same thing, but for your legs/knees. When it's too cool to leave your knees exposed but not so cold as to require a full-length tight, these warmers are just about perfect. I purchased the large size, which is the recommended size for men. They fit well with one caveat: There's a rubber-like edging on the upper cuff that's meant to keep the warmers from slipping and sagging. I get the best results when I position that edging above and underneath the lower cuff of my cycling shorts. When I do this, the warmers stay put. Not sure how well they would stay put if you don't wear cycling shorts on top. Warm, not itchy, and easy to care for. What's not to like?
Date published: 2012-10-24
Rated 5out of5
by fromComfortable and Lightweight I get hot very easily, so the idea of wearing cycling tights/pants did not sound too good. I've also seen my friend friends wear leg warmers and when they took them off and packed them in their back jersey pocket, they would stick out like a shark fin. With these, I was protected from the chilly night wind. I wouldn't say I was warm, but I wasn't cold. They also gave a compression like feeling. And when I wanted to take them off, they fit in my jersey pocket like my jacket did, flat against my back. Awesome product!
Date published: 2012-11-14

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