Our spiral baffle exhaust flex pipe is made of overlaying braids of steel that reduce noise from the exhaust system. Inlet/Outlet Diameter: 1.75" : Flex pipe Total Length: 6". You can directly attach this flex pipe to the end of the exhaust pipe with no modification to the car. There is no instruction manual; professional installation is highly recommended. Free shipping for this item available only in the continental United States. For Puerto Rico, Alaska, and Hawaii, please contact us first for a quote.