4" reverse-cone megaphone muffler body with matching billet end cap 1-3/4 head pipe steps up to 1-7/8 into the collector to increase flow and improve performance Removable spiral-core louvered baffle included Features hand MIG welding 18mm and 12mm O2 ports with adapters and plugs Includes mounting hardware and full heat shields Made in the U.S.A.. EXHAUST 2:1 MEGA BK 95-06