Filtrete High Performance Air Filter 1500 MPR 2005-4, 14 in x 20 in x 1 in (35.

OUTPERFORMS FIBERGLASS, WASHABLE AND NON-ELECTROSTATIC 3-month pleated 1 in. slim fit and 5 in. filters, and at least every 12 months for 4 in. filters - A dirty filter will slow down air flow and make the system work harder to keep you warm or cool--wasting energy.

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