Aerostar 16 3/8x21 1/2x1 MERV 8 Pleated Air Filter, AC Furnace Air Filter, 2PK

Nominal Size: 16 1/2x21 1/2x1; Actual Size: 16 1/2" x 21 1/2" x 3/4" Comparable to MPR 600 Clean Living and Honeywell Micro Defense Plus FPR 5 Designed to filter microscopic particles such as lint, dust mites, spores, and pollen. Simple to install and a cost-effective step towards a healthier home environment. For best results, change your filters every 60 to 90 days but increase frequency to 30 days during peak summer and winter months 100% synthetic electrostatic media for high efficiency with low air flow resistance