A beverage board die cut frame holds an expanded media pad of continous glass fibers in a progressive density pattern. This design results in a relatively open fiber spacing on the air entering side progressing to a more dense fiber spacing on the air leaving side.

“5700” die cut construction filters are designed for general air filtration in industrial and commercial HVAC systems where metal retainers are not required. Built for long-lasting service life, this heavy duty, double-wall construction filter is suitable for installation where dust loading conditions are particularly heavy. "5700” filters also serve as excellent prefilters for higher efficiency filters.