Milltek catback system resonated with T304 grade stainless steel, mandrel bent and TIG welded 2.5" / 63mm pipework that fits from the OEM or aftermarket catalyst with Cerakote Black 3,15" / 80mm GT80 tailpipes.Direct bolt-on100% T304 grade stainless steelTIG welded2.5" / 63mm pipeworkGT80 Cerakote B..