American Air Filter Blue Polyklean Filter Roll measuring 24" X 90' X 1" is made of Standard loft polyester media for durability. Filter roll has an extremely large amount of fiber surface area of intersections and intricate fiber structure holds more dirt with less resistance. It has pressure sensitive dry tack adhesive applied on the air leaving side for added performance. Polyklean filter medias are widely used in commercial HVAC systems and unitary equipment involving medium to heavy dirt loading conditions. It also functions as excellent prefilters and as prefilters it removes larger, heavier particles that would quickly plug up Standard efficiency filters. Economic polyklean filter roll is designed for custom sizing and installation in permanent metal frames. It operates in temperature up to 175 deg F.