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Aerostar 13x21 1/2x1 MERV 8 Pleated Air Filter, AC Furnace Air Filter, 6 Pack (Actual Size 12 7/8 x 21 1/2 x 3/4 )
Nominal Size 13 x 21-1/2 x 1; Actual Size 12 7/8 x3/4 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

Price is $56.00
Price: $55.57