You Will Feel the Difference! Breakthrough product specifically designed for comfort, fit, protection and breathability. OS1st TA4 Thin Air Performance Socks feature never before applied technology to keep your feet cool and protected during any activity. Created using 200n medical grade machinery and materials we are able to build in comfort, durability and blister protection, yet with the thinnest upper foot profile ever made. The "Thin Skin" construction with uniquely positioned lift-bars, maximizes air-flow achieving a cooling sensation to your feet. Our OS1st manufacturing technology has been leveraged to create the most unique performance socks ever! We alone or pair with our OS1st TA6 Thin Air Performance Calf Sleeves. Buy a pair of TA4 Thin Air Socks and get a pair of TA6 Calf Sleeves for 15% off. Lightest Cushioned Performance SockSheer areas to increase air flowMoisture wicking - PerformanceBreathable - FreshnessAnatomical left/right design - Fit STAY ACTIVE, COOL and COMFORTABLE with OS1st Thin Air Performance Socks featuring breakthrough Skin Thin construction. Maintaining an active lifestyle requires products that fit your daily schedule and can help keep up with your active pace. OS1st Socks with Purpose are designed for just that reason. The OS1st TA4 Thin Air Performance Socks were strategically designed to be the world’s thinnest running socks without compromising fit and feel. Still providing OS1st’s standard of quality, the thin air performance socks have a high performance cushioned sole providing a blister free experience. These patent pending socks are made with all the best features you normally find in your favorite running socks…moisture wicking, odor control and blister protection, but now, OS1st has combined those features with our patent pending air movement system design. OS1st TA4 socks are lightweight, cooling and protective. BREAKTHROUGH DEVELOPMENT IN COMFORT…YOU WILL FEEL THE DIFFERENCE! The OS1st TA4 Thin Air Performance socks feature 4 zones of graduated light compression, a shaped-to-fit design for all foot types made with ultra-soft yet durable microfiber. These socks will amaze you with the patent pending air-flow system within the super thin upper and lower zones. No binding, no bunching, no pinching…just the perfect fit for enjoyment of your active lifestyle. The high heel tab and extra deep heel pocket prevent the socks from slipping down inside the shoe for better overall experience.