MagnaFlow Custom Clamp on tips are sized for specific tailpipe diameters completing most any exhaust system with the just the right finishing touch. MagnaFlow 4in. Round Black Coated Exhaust Tip 35236 is made of durable stainless steel and built using CNC precision robotic manufacturing techniques all backed by MagnaFlowâ€s limited lifetime construction warranty and 1 year finish warranty.