Strideline Utility Running Socks Nylon Polyester Cotton Pocket Secured with Premium Patented StrideTec Materials Allowing for Maximum Comfort and Durability. 100% Satisfaction Guaranteed. Contact us at sales@strideline.com or 206 734 6870 with questions. Nate Robinson x Strideline create the worlds first sock with a compression pocket Pocket big enough to hold your credit card, keys, ID, cash and more Perfect for traveling and going to the gym Get a perfect fit everytime with Left/Right anatomical construction