Deathmat is comprised of non-cured Butyl Rubber with an Aluminum top layer for efficient damping and a clean install. A difference will be noticed with as little as 50% of the panel covered with Deathmat. Obviously, the more you use, the more "dead" the panel gets. The "deader" the panel gets, the less road noise you will here, the less vibration you'll hear from the body, and the cleaner and clearer your system will sound. You will also even notice an increase in SPL. Deathmat kill unwanted resonance!