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Run without worrying about the pruned, stinky-feet side-effects you used to suffer; you received your doctorate in good sense when you pulled on the SmartWool PhD Running Ultra Light Mini Sock. This thin sock provides ankle coverage while still allowing your lower legs breathing-room on hot days.

  • Blended composition maximizes the benefits of each separate material while minimizing fabric drawbacks
  • Soft merino wool breathes well, helps regulate body temperature, and is naturally odor resistant
  • Nylon components dry quickly, breathe well, and add extra durability
  • 4Degree Elite Fit system employs ankle, instep, and arch elastic bands for a snug fit, support, and circulation
  • ReliaWool tech on the bottom of the sock combines high-density impact zones along the ball and heel for long-lasting protection
  • Mesh zones allow heat and moisture to escape quickly to promote faster drying to reduce swamp foot
  • Virtually seamless toe construction limits irritation and chafing

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Here's what others have to say...


The wife loves them

  • Familiarity:I gave it as a gift but have feedback to share
  • Fit:True to size
  • Height: 6'2"
    Weight: 180 lbs

If you want cool, comfortable feet rather than sweaty, clammy feet I strongly recommend you purchase a pair of these! You won't regret it.


5 Stars and Two Thumbs Up

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

I got the PhD Cycle Ultra Light sock and decided to get something a bit higher for hiking and trail running. These are super thin and wick away the moisture extremely well. I have yet to get any blisters using these socks as they tend not to bunch or rub. Best socks I've ever owned. Treat your feet right and pick up a pair.


comfy running sock

  • Familiarity:I've used it several times
  • Fit:True to size

cant go wrong with smartwool....very comfy and breathe-able.


Perfect balance

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

This sock has become my all time favorite. I bought it for running but now wear them all year long. Don't let the "ultra" light part throw you off. This sock is the right thickness and provides great fit, comfort, and performance. The PhD light is just too thick.

I currently own about 25-30 pairs of this sock, some going back about 4 years.

My only complaint is that the top collar of the newest version isn't as snug as previous years but that is splitting atoms.


Great for all seasons

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

I bought these last year for winter but actually wear them all year around. They are soft and comfortable for all day use too in the office. Best for running and also in the gym.


Awesome Sock!

  • Familiarity:I've used it several times
  • Fit:True to size

This is a really great sock. It holds well, has a bit of cushion, and wicks away sweat. For the price, you're getting everything you paid for. I will certainly buy more of these in the future.


light and comfy

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

when things get real hot these socks rock! super soft and comfy. They have also held up well to abuse so no complaints. I also like the higher ankle length to them


Super Light

    This is a great sock to run in. It is very light and compresses on your foot creating a snug feel.