Extension pipe 60692 is used to adapt Cat-Back? systems 140798 and 140798BC to Super Duty trucks with an Extended Cab Standard (8') Bed 164" Wheelbase. Will NOT fit vehicles with dual rear wheels. 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 apatper/ extension pipe with a Million-Mile Warranty. Just what you?d expect from the world?s most experienced (and most winning) exhaust brand.