Pre-Filter Air Make-Up Bag: Is a heavy duty, internally supported filter made from progressive density polyester fiber. This filter removes over-spray from lacquers, air-dry enamels, and thermo-reactive coatings. Full depth loading provides 99.8% removal efficiency. Expanded filter surface area due to pocket/cube configuration results in high paint-holding capacity and long service life. Excellent alternative to paper exhaust filters due to resistance to moisture. Available in various configurations to meet each spray booth's unique specifications.