The Central Vac E101 E-series Filters is a pre-filter that catches fine dust particles and protects the Cyclofiltre. The Cyclofiltre with antimicrobial treatment prevents the growth of mold, fungus and bacteria, captures micro particles and protects the motor. This Cyclofiltre is machine washable and reusable. The Central Vac E101 E filter is hand washable and reusable.