Uppers are twin faced sheepskin with suede heel guards. Outsoles are molded EVA that is very light and flexible. Note: These boots are not for wider widths. Small opening. Because of the small opening to put boots on please grasp the back loop and insert foot while pulling on loop. This should help the foot glide into the boot. Once the boots have been put on a few times putting them on gets easier. UPDATE! Chocolate boots now come with Dark Brown sole!