Filter bags are one of the most efficient ways of collecting smaller particles of dust from an airstream. The fine pores of this DC-250 cloth filter bag allow air to pass through while leaving behind dust particles in the air. Typhoon dust filters are micron rated and made from a variety of materials from woven felt to polyester giving a range of filtering capabilities from 30 micron down to 1 micron. Dust caking on the inside of the filter bag eventually causes the bag to become unusable and a replacement filter will be required. Every Typhoon dust collector and baghouse uses a filter bag of a specific size for separation of dust from the air.