Peace be upon you I have a Sierra catback From 2007 to 2018 Original Fox Skyline, purchased for 1200 without detailing the cat 3 inches, no back pressure It goes 140 when closed, it doesn't suffocate or harm The outlet and outlet are original, custom-made Customized by Bin Mardah and the complete 3-inch cat Its sound is not annoying and it has a nice tone The muffler is, in short, new Note: The sound is the same as its sound and vibration Only serious buyers should message Only serious buyers should message Only serious buyers should message