Porter Cable PXCM019-0279 air filter Element - 1 piece is a member of the Porter Cable line of genuine replacement parts. A filter Element is designed to allow air to be pumped cleanly and efficiently. This keeps the compressor and air tools being used running smoothly and efficiently. The Porter Cable air filter Element - 1 piece is to be utilized when the air tool in use is not getting enough air or pressure. Simply replace the old, plugged filter elements with a new Porter Cable air filter Element - 1 piece and eliminate the issue of the old filter Element causing problems. Replacement of filters should be done to keep the unit running at its highest level.