Running has never been so easy as with the X-BIONIC® SOCKS XBS.EFFEKTOR RUN 4.0. The footbed of these running socks effectively works with every step to maintain your performance level. This is achieved through targeted stimulation of the soles of your feet. The brain responds by sending more signals, which leads to an acceleration of metabolism and improved blood circulation. With the X-BIONIC® SOCKS XBS.EFFEKTOR RUN 4.0 WMN from X-BIONIC®, blisters and chafing on your feet are a thing of the past. Designed to elevate female athletes to the next level, the sock integrates the 3-Expand LadiesStripes and the Narrow Arrow construction, which are specifically tailored to the anatomy of the female foot. They are produced on special knitting machines to accommodate the slimmer shape. A patented system of cooling channels ensures that your foot stays at the perfect working temperature mile after mile. A total of 14 patents and technologies for stability and air conditioning are integrated into the running sock to optimize your performance.