The Run Anatomic Crew sock is built to enhance comfort during your effort. All the essential benefits expected for running have been incorporated into the sock design: Breathability under the foot where heat is important, ankle support to prevent injury and fatigue, In and out" sock construction to avoid extra thickness between foot and sole for better feel. Thanks to our database of over 400,000 scanned feet, we have developed a unique range of socks to reinforce the benefits of insoles: stability and sensation. Comfort: The socks have been designed using our foot expertise. Polyamide Microfilament and construction avoid excess material underfoot making the sock particularly comfortable from the very first moment. Thin and strong: The socks have a very thin construction thanks to our Synergy Fit design, making them one of the lightest in their class. They are made with a very high quality yarn to make them strong and durable. The socks come with a 2-year guarantee."