Just like our air filters, this 1/2” open cell polyurethane foam pre-filter is washable and reusable. Just simply tap to remove excess debris between your usual cleanings, and then wash it with aFe POWER Cleaner when you service your air filter. pre-filters provide added piece of mind for those who operate their vehicle in dirty environments. This foam example captures large particles before they reach the air filter – increasing efficiency and dust holding capacity, without negatively affecting airflow. For even further protection, it can be oiled with aFe’s air filter oil.