11.5x29.5x.75 actual size (12 x 30 x 1 nominal size). Our 12x30x1 air filter is an extended surface pleated filter, which outpaces ordinary air filters with medium efficiency, and are engineered for decreased pressure drop, and longer service life, which reduces HVAC equipment maintenance and energy expenses. Our 12x30x1 air filter is rated to ASHRAE test standards 52.2, which ensures that the air filter will capture particulate as good or better than original manufacturer 12x30x1 air filters. Pleated design. MERV classified to ASHRAE classifications. 738 cfm flow rate.