11.5X14.5X.75 actual size (12 x 15 x 1 nominal size). Our 12x15x1 air filter is an extended surface pleated filter, which outperforms ordinary air filters with medium efficiency, and are designed for decreased pressure drop, and extended service life, which reduces HVAC equipment maintenance and energy costs. This 12x15x1 air filter is graded to ASHRAE test standards 52.2, which establishes that the air filter will capture particulate as good or better than original brand 12x15x1 air filters. Pleated design. MERV tested to ASHRAE standards. 369 cfm flow rate.