These 2.75" diameter Tail Pipes are intended to add the Dual Mode Exhaust (NPP) valves to Borla systems 11920, 11921, 140687, and 140688 that did not come with NPP valves. They feature 4" polished T-304 stainless steel tips. They can only be used with mufflers that have dual tips exiting the mufflers. These pipes replace the outside tail pipe on each muffler. Outside tail pipe on 11920, 11921, 140687, or 140688 must be cut off of the Axle-Back assembly in order for these tail pipes to be installed. Clamps included. Wiring and actuators are not included. They are NOT intended to add NPP to a vehicle that was not originally equipped with NPP. 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 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.