These 2.75" diameter Tail Pipes are intended to add the Dual Mode Exhaust (NPP) valves to Borla(r) systems 11920 11921 11926 11927 140687 and 140688 that did not come with NPP valves. They feature single 4" round polished T-304 stainless steel tips on each tail pipe (2 tail pipes included in this kit). They can ONLY be used with Borla(r) mufflers that have dual tips exiting the mufflers. These pipes replace the outside tail pipe on each muffler. Outside tail pipe on 11920 11921 11926 11927 140687 or 140688 MUST be cut off of the Axle-Back assembly in order for these tail pipes to be installed. They are NOT intended to add NPP to a vehicle that was not originally with NPP. Wiring and actuators are NOT included. Built from premium high-quality T-304 austenitic stainless steel superior to T-400 series knockoffs (such as 409) to give you the absolute best in performance and durability. Ultra-smooth mandrel bends ensure maximum flow & power and precision computer numerical control (CNC) manufacturing ensures an accurate fit. Best of all Borla(r) stands behind every Tail Pipe with a Million-Mile Warranty. Just what you'd expect from the world's most experienced (and most winning) exhaust brand.