The Reebok CrossFit Oly U-Form is one of the lightest Olympic lifting trainers on the market. Full-grain leather toe offers durability. Durable nylon midfoot support strap provides added stability. U-Form Custom Fit Technology adds excellent fit. Perforated medial and lateral upper components deliver increased breathability. Semi-rigid forefoot allows for flexibility and multi-functional use. Injected TPU heel wedge. PU molded sockliner brings increased support and comfort. Injected TPU heel wedge with carbon rubber outsole gives lightweight stability and traction. Wt. 11.9 oz. U-Form Instructions: 1. Pre-heat oven to 200 degrees Fahrenheit (93 Celsius). 2. Heat shoes for three minutes (U-Form tab will turn red). 3. Remove shoes from oven. 4. Lace up shoes as you normally would and wear them seated for eight minutes. (U-Form tab will return to black) 5. Let the shoes stand for about an hour or until completely cooled before wearing them.