Empi's 1-5/8 Diameter Mandrel Bent Tubes Are Cut And Fitted Into A Long Merged Collector For Smooth Flow A True High Flow Performance Exhaust System. Note: Discoloring Is Not A Manufacturing, Chrome Process, Ceramic Coating Process Or Stainless Steel Defect Issue. High Exhaust Temperatures May Exceed The Capabilities Of Chrome Plating, Ceramic Coatings And Stainless Steel Materials Resulting In Discoloring Or Bluing In Color.