The RANGER SILVER 82 is designed to meet the special needs of some furnaces and air conditioners that require a very low resistance due to a limited return configuration. The 0.08 inch W.G. initial resistance of the RANGER SILVER 82 will assure sufficient air flow to minimize concerns about freezing coils or overheating heat exchangers. The woven polypropylene layer with integral anti-microbial material provides 8 times more filtration than a disposable filter. The non woven polyester prefilter will maintain high arrestance even when soiled.