Tesla Model S Carbon Fiber Rear Lower DiffuserMDI Carbon Fiber Rear Lower Diffuser for Tesla Model S Replaces the original Chrome Diffuser below the lower plastic bumper. The lower plastic bumper is available separately. All our carbon fiber Rear Lower Diffuser are made with an Autoclave process, which uses the highest quality TORAYCA PREPREG carbon fiber fabric from Japan. More information on the manufacturers specifications: Finishes and Materials! Cures at 400 degrees and a pressure of 5Kg cm.