Bassani Xhaust 2-Into-1 Mid-Length Super Bike Exhaust System - Stainless Steel781129217 Product Description Hand TIG welded stainless steel construction 1 3 4" headpipes step up to 1 7 8" into the collector to increase flow and improve performance 4" diameter straight can 11" muffler body includes matching aluminum end cap Removable spiral core louvered baffle features an aggressive sound 18 mm and 12 mm O2 ports with adapters and plugs Partial heat shields and mounting hardware included Made in the U. S. A.