It also produces acrylic glass, polystyrene, thermoplastic elastomer and synthetic rubber. A portable cord is usually made of thermoset polymer, thermoplastic elastomer, or thermoplastic. Natural rubber is an elastomer and a thermoplastic. TPU is the thermoplastic elastomer used in FFD fused filament deposition 3D printing. Polyether block amide or PEBA is a thermoplastic elastomer (TPE). This is the reason such a material is called a thermoplastic elastomer (TPE). It is a polymer of isoprene which forms a rubber-like elastomer. A synthetic rubber is any artificial elastomer. Generic or custom-fitting ear canal plugs are made from silicone rubber, elastomer, or foam. Fenders are typically manufactured out of rubber, foam elastomer or plastic. In 2007, silicone rubber formed the matrix of the first autonomic self-healing elastomer. As a durable elastomer, EPDM is conformable, impermeable and a good insulator. The cis structure of polyisoprene is the common latex elastomer. Polysorbate 20 is also used as wetting agent in rubber balers in the elastomer industry. Another key improvement was to connect them to a short piece of silicone elastomer tubing.