Heeled platform loafers new never worn w tags Composition Lining:Polyester 100% Sole:Thermoplastic rubber 100% Upper:Polyurethane 100% Materials in this product explained Polyester Polyester is a synthetic fibre made from crude oil (a fossil resource). Polyurethane Polyurethane (PU) is a synthetic material made from oil (a fossil resource). Thermoplastic rubber Thermoplastic rubber (TPR) is a synthetic rubber made from a type of polymer (a fossil resource). It has the characteristics of both rubber and plastic.