SilentMaster features HyperFlow filtration. filter bags are a 3-ply microgeometric technology. They are not made like typical paper bags, but are a woven cloth-like material. HyperFlow is engineered for most airflow while still functioning as a filter. Silent- Master’s 1,500 square inches of filter surface area allow sustained performance and fine micro-filtration. The unique tapered design of the filter allows air to be drawn in from the sides of the filters rather than through the debris.