Nanofiber Filter, Filter Type Disposable Filter, Filter MERV Rating 15, Compatible Extractor Series Filtair MWX-D, Filtair SWX-D, Compatible Extractor Manufacturer Part Number 300599, 951507, 951508, 951509, 951513, 951514, 951515, 951619, Compatible Extractor Grainger Part Number 4VDJ4, Features Designed Specifically for Weld Fume, Surface Loading Design, Ultra Efficient, Filter Area 490 sq ft, Filter Efficiency 95 Percent, Filter Media Cellulose