Reebok NFL U-Form 4 Speed Mid SD4 Men's Football Shoes fabric-and-synthetic U-FORM footwear lining technology that, when heated, shapes to your foot for a customized fit which ensures stability and reduces slippage inside the shoe. Soft, synthetic performance leather upper for comfort, lightweight feel and minimal break-in. Studded TPU outsole for maximum traction and propulsion. Mid-cut design for increased stability and handling. Heating instructions: 1) Heat shoes in a conventional oven at 200 F for 3 minutes; 2) put on shoe, lace it up tight and sit 8 minutes while shoe forms to foot; 3) after one hour, once shoe has cooled, your custom-fitting shoe will be ready for game time.