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The same ridge you skin up in the winter becomes the venue for your summer runs when you slip on the Dynafit X4 Speed MTN Sock and let your feet do all the work. Between your foot and your trail running shoe, this ultralight sock provides the dynamic interface to keep your foot dry and ever-prepared for the next stride on the loose scree trail.

  • Ultralight, stretchy polyamide and polypropylene blend fabric with mesh panels allows ample breathability, moisture management, and quick-drying performance on long runs
  • Silverized Technology fights odor-causing microbes so your foot and shoe remain fresh throughout the summer
  • Dynafit compression enhances blood flow and oxygenation to your muscles as you train or race, as well as help to speed up recovery time afterward
  • Seamless design prevent chafing and blisters during all-day runs
  • Light cushioning on the sole aids your steps when you're running on rocky trails
  • Elastane provides two-way stretch and arch-hugging structure to match your foot's natural shape and to prevent movement and blistering
  • Calf height provides compression to your lower leg to enhance your running performance

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Here's what others have to say...


Terrible product

    They tear easily. Worst of all they cut off circulation. I'm a size 29.5 boot and the large sock runs very very small. I use Dynafit Vulcan boots which are amazing. I'm a Dynafit lover but this product is a no go. I had to give it one star in order to post my review but I would give it a zero star rating.


    Great performance for 1 season

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

    This is a great spring sock. It is not for cold days. If your boot fits well it has great calf compression and fits well. One of the socks started getting a big hole in the toe after about 15 days/washes. Good performance but that's a short lifetime for a sock.