Pad Refills (Pack of 6 Pads) - 20" x 20" x 2" Quantity:Default Filtering inserts are anti-microbial and

Filtering inserts are anti-microbial and are more efficient in capturing particles

Either way

And there are no metal parts that could lead to corrosion or oxidation within the filter

Available in packs of 4

This is designed to fit into 1" Return Air Grilles

Pad Refills (Pack of 6 Pads) - 20" x 20" x 2" Quantity:Default Filtering inserts are anti-microbial andPACK of 6 pads for Pad and Frame Air Filters Filtering inserts are anti microbial and are more efficient in capturing particles, such as dust, ragweed, pollen, etc., from the air stream, than standard fiberglass filters purchased at retail outlets. Filtering inserts are shipped in an easily stored packet.