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Ultra light, micro cuff.

You’re sweating and you haven’t even started running yet—that’s how hot it is out. Is your foot sweating? Naw, it’s cool inside the Smartwool PhD Running Ultra Light Micro Sock. This super-lightweight sock uses vents on the top to take care of excess foot heat, Wool-on-Wool technology to beef up shock-absorption on the heel and forefoot, and thin wool to manage moisture and block odor. Plus the mini cuff prevents shoe rub without covering all of your ankle.

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Review Summary
14 4
9 3
2 2
2 1

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SmartWool PhD Running Ultra Light Micro Sock

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Here's what others have to say...

5 5

god for running

  • Gender: Male
  • Familiarity: I've used it several times

I have used the socks for long runs. They don't roll down and do wick the moisture away from my feet

4 5

Good, but thin

Don't get me wrong, this is a great sock. I have 2 pairs and I wear them for everyday use when it's hot out. The part I don't like is that they are too thin for running or active activities; mainly because there isn't the cushion that SmartWool is known for in their socks.

For those looking for a thicker, but still ultra-light sock, I recommend the SmartWool PhD Running Ultra Light Mini Sock. Difference is they are slightly thinker given you the extra cushion and they sit at the ankle vs under the ankle as in the micro socks.

2 5

Quality -- not so good

Wore out fast unlike most smartwool products

4 5

Great socks for the right use

These socks have a lot going for them. They're merino, so they won't stick. They're thin, so they don't bunch up on you or weigh you down. However, there is not much padding, so if you're a plodder, these might not be best for you.

4 5

Got the job done

Good socks. Kept my feel dry and cushioned in my shoes during day hikes. Only lament is how filthy they had become at the end of the day without spending a lot of time on unpaved trails. After one use and wash they fuzzed up quite a bit and I wonder how long they'll last.

2 5

Holes in the first week

I just wasn't impressed with how long these lasted. I had holes in a pair after one week. Maybe I was too tough on them, lightweight hiking, but, hey, they are socks. My two other pairs of SmartWool have worn out faster than I would have liked also. SmartWool, please make your socks last longer and tell me when you do. Until then, I will be looking elsewhere.

4 5

Very comfortable, quality could be better

My first impression of the SmartWool PhD Running Ultra Light Micro Sock is that they were very comfortable, provided great arch support, wicked away perspiration and didn't smell after a long day of hiking. My only complaint is that after only two days of use, the sock material began to pill and wear.

5 5

Great summer socks

I use these socks mostly for running and hiking but they are comfortable enough that you can use them for whatever. And it is true what everyone says, they do last about a solid week before they start to smell. My only problem is that I now refuse to wear anything except wool on my feet.

5 5

Smartwool is top notch

Comfortable, stink free and wicking. What more could you want from a sock? Smartwool delivers a great product, once again.

3 5

Wear out quickly

A very good sock, while it lasts. They wore through very quickly and needed to be replaced. Gets quite pricey.

5 5

Good sports sock

I wear these playing Ultimate, and while they're pricey, They have held up great. After six or so months they're in great condition, and can last at least another six. Worth the price, I've always been impressed by smartwool

5 5

A Warning

First off, these are the best socks I've ever worn. They are extremely comfortable, manage moisture well and I can wear them for a week straight before they need to be washed. I wear them for working out, running, hiking and around town. Second, if you are a typical college student, don't buy these (or Smartwool in general) because you will be poor. You won't really be satisfied with any other sock so you'll be screwed. I'm only kidding though so don't listen to my stupid review and buy some already.

5 5

Great hiking socks

I switched to hiking in trail running shoes a few years ago, but just started using light weight wool socks. What a big difference! These are great at moisture wicking and protect my feet from friction. I wear and 8 shoe and bought a M sock. It fits perfectly after 3 washings. The profile is low, but with my XT Wings they have enough coverage. I just ordered 3 more pairs!

5 5

Great socks

That is all there is to it, they are great! I love running and hiking in them.

5 5

yay wool

I was a fan of the PhD ski socks, so I figured I'd try these. This sock fits great, and the wool definetly resists the funk and quick wearout that is common for synthetic socks. Good moisture management, too. I like the extra bit of material in the rear of the ankle because it keeps the sock in place and guards against shoe rub a bit. These socks stay put pretty well for a low cut sock.

5 5

The Dr. is in

I have used the Adrenaline Light Micro for several years and was skeptical when the PhDs came onto the market. I bought a pair a few weeks back, tried them and returned to the store to buy two more pairs. They are everything I have come to expect from SmartWool and have surpassed the adrenaline line in comfort and mainly there ability to stay put. You can expect trails debris in your socks, but not a huge issue in my book and easily remedied with gaiters or a little attitude.

5 5

Perfect socks

These are perfect socks. Worth $12.50 (or however much). I wear one pair for as many as 4 or 5 days in a row, no joke. No heavy sweating like with cotton socks, no stinking. I've slowly been adding more and more wool no-show socks and phasing out the terrible, inferior cotton ones.

I wear a size 9 shoe and Mediums are a perfect snug fit. Worth every penny. Get them

5 5

Great socks

I love Smart wool products and these are no different. After using their ski and snowboard socks for years I decided to venture into some running socks. They are light and breath well and the material glides well to protect my feet from blisters or hot spots. I run a few times a week from 2-5 miles and wil never go back to another sock, as long as I can afford them.

4 5

Good for a low cut sock

I prefer quarter length socks, but I thought I would give this a try. They turn out to be a very comfortable sock that doesn't chafe. Merino wool is always a plus too!

5 5

Best low socks I have ever had!

Smartwool has once again made my feet very very happy. I easily forget I'm even wearing them. they let my feet breath and stay cool. Even in winter my feet stay warm with them on. Ah the magic of wool. I have switched exclusively to wool socks, and i will never go back to uncomfortable cotton

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