Trask 2-Into-1 Nasty Bastard Exhaust System990429307 Product Description 1 3 4" header pipes flow in a tapered 3" to 3 1 2" turnout megaphone 37" L with 3 1 2" billet end cap Includes performance baffle Made in the U. S. A Notes 18 mm to 12 mm sensor bung adapters not included. Must be purchased separately if required Does not include O2 sensor port plugs for non sensor applications