VRSF 4.5" F20 B58 Stainless Steel Catless Downpipe: Made from hand crafted, tig welded 304 grade stainless steel. Direct bolt-on application. Smooth radius bends to decrease turbulence and increase flow. Fits the stock catback as well as all aftermarket catbacks that mate up with the OEM downpipe. CNC SS304 stainless steel flange. Gains from 20-25hp with tune. VRSF Lifetime Warranty. Applications: 2016+ F20 BMW M240i & M240i xDrive Model Number: B58EX100