Glasfloss Z-Line Series Air Cleaner Replacement Filters offer convenient alternatives when replacement of the original filter is necessary. The mechanical structure of the media fibers sustains efficiency over the service life of the filter and produces high dust-holding capacity. All Glasfloss Z-Line pleated filters feature fibers which do not absorb moisture and will not support microbial growth. The Glasfloss Z-Line Series 700 SG filters achieve a MERV 8 per the ANSI/ASHRAE 52.2-2007 Test Standard.