PerfectPleat SC M8 filters are designed to consistently increase efficiency throughout the service life of the filter. They have an initial MERV 8 rating respectively, but the efficiency increases significantly when dust loading begins. PerfectPleat SC M8 filters have distinctive self supporting characteristics that allow a pleating pattern, which promotes airflow and maximizes dust holding capacity (DHC). The PerfectPleat SC M8 filter is best suited for standard capacity pleated panel filter ap plications, where pleated filters are currently in use. They can also be used to upgrade applications using panel filters.