aFe 49-36314 MACH Force XP Cat-Back Exhaust for BMW M3/E46 L6-3.2L S54 Engine 2.5 inch stainless steel; 100 percent hand TIG-welded Manufactured and assembled in USA Includes 4 aFe laser etched, 3 inch slash cut polished 304 stainless steel tips X-pipe balance tube equalizes and evenly distributes exhaust pulses No modifications necessary; uses factory hanger locations for hassle free installation