15.8125X31.8125X.75 actual size (16 x 32 x 1 nominal size). Our 16x32x1 air filter is an extended surface pleated filter, which exceeds ordinary air filters with medium efficiency, and are built for lower pressure drop, and increased service life, which reduces HVAC equipment maintenance and energy costs. The 16x32x1 air filter is classified to ASHRAE test standards 52.2, which establishes that the air filter will capture particulate as good or better than original manufacturer 16x32x1 air filters. Pleated design. MERV graded to ASHRAE grades. 1048 cfm flow rate.