This is an authentic manufacturer-sourced component which is specially designed for use with Dynabrade sanders. The purpose of this muffler is to reduce the noise coming from a working unit, unfortunately, over time it will wear out and it may begin to fail eventually requiring a replacement. Keep in mind this high-quality cone muffler is...Read more sold individually. Please make sure to refer to the appropriate diagrams of your model for the correct location and application of this hardware.