S-class filters are made from electrostatically charged micro-fiber material, which attracts and captures dust particles from the airflow of the vacuum. The S-class Standard requires filters to absorb greater than 99.9% of particles down to 0.3 microns in diameter. Their advantages are a relatively open texture that allows smoother airflow for better suction performance, a long-lasting life expectancy, and they typically cost less than HEPA filters.
