This is one piece of N1 style straight muffler and it's made of 100% high quality T-304 stainless steel with titanium burnt tip. This muffler fits most cars with 2.5" inlet (usually for non-turbo engines and exhaust with 2.5" inlet). Please make sure the inlet size of your car before purchase. Also see dimension below. Getting more air into your engine and more exhaust out is the key to a performance motor. That's where exhaust muffler is significant as the tip of an exhaust system. Larger exhaust tip means higher air flow efficiency, which prevent the backpressure that occurs in a common exhaust system. When cylinders don't have to fight with each other to expel their exhaust, they can put more power through the wheels with the very minimum restrictions and your engine will perform at its potential. This muffler will increase about 8%-10% horsepower and will produce a smooth deep throaty tone. Sound level varies, depending on piping diameter and type of resonator. Installation requires cutting the old muffler in order to weld on the new muffler, extended pipe might be needed for some cases and it is not included with this package. Please check the measurement below or inquire your mechanic if any extra pipe is needed for your vehicle. We highly recommended professional installation.