This muffler is a genuine OEM replacement part sourced directly from the manufacturer for use on lawn and garden equipment. It reduces the noise coming from the exhaust. Being a metal part exposed to the elements, it is not uncommon for mufflers to corrode over time and need replacement. As a lawnmower part, the muffler may sustain damage from debris in the yard while mowing. In either case, the muffler should be removed and replaced to keep the noise level to a minimum.The engine and damaged muffler should be cool to the touch before repairing the lawnmower. Wear work gloves and safety goggles. Remove the spark plug from the lawnmower for extra safety. Locate the bolts securing the muffler to the lawnmower and loosen them to remove the muffler. Dispose of the old muffler and align the new muffler with the bolts. Attach the new muffler and tighten the nuts. Put the spark plug back in the lawnmower. This muffler is a high-quality metal part that is individually sold. It does not come with hardware. It is designed for use on lawn mowers and lawn tractors manufactured by MTD, Ryobi, Yard Machines, Bolens, Yard-Man, Troy-Bilt, Poulan, and Husky.