The fumes are drawn through the bags from outside and a layer of dust accumulates on the filter media and clean air is filtered out from inside. When a sufficient differential pressure occurs the cleaning process begins. There are two types of Bag House, Process and Nuisance and operational type also two, ON-Line System & OFF-Line System. Enviro-Treat provides excellent quality non woven double stitched Snap-Type Filter Bags that ensures better durability and performance.