EZ Flow Air Filter, Spun Fiberglass, 30 Days,21.5x21.5x1-In.

21-1/2" x 21-1/2" x 1", EZ Flow Spun Fiberglass Disposable Furnace Filter, Flat Panel, Metal Retainer On Air Exit Side, Only Up To MERV Rating 4, 30 Day Filter, Effective Against Dust/Lint.