Using this Invidia Dual N1 cat - back exhaust is a breeze. First, turn off your car and let the engine cool down. Then, remove the old quiet exhaust from your 2011 - 2014 Subaru Impreza WRX Hatchback or 2008 - 2014 Subaru Impreza WRX STi Hatchback. Install the Invidia N1 exhaust by using the provided new gaskets and hardware. Make sure the exhaust hangers fit onto the OEM locations. After installation, start your car to check if everything is working properly. When it comes to maintenance, regularly check the gaskets and hardware for any signs of wear or looseness. Keep the 304 stainless steel construction clean to prevent rust. If you notice any unusual sounds or performance issues, it's a good idea to have it checked by a professional. Also, remember that if you're using the factory downpipe, you'll need an appropriate cat - back adapter.