Extension pipe 60693 is used to adapt Cat-Back? systems 140798 and 140798BC to Super Duty trucks with a Crew Cab Standard (8') Bed 176" Wheelbase. Built from premium T-304 stainless steel, superior to T-400 series knockoffs (such as 409), to give you the absolute best in performance and durability. Precision computer numerical control (CNC) manufacturing ensures an accurate fit. Best of all, BORLA? stands behind every adapter/ extension pipe with a Million-Mile Warranty. Just what you?d expect from the world?s most experienced (and most winning) exhaust brand.