19x27x1 Exact MERV 13 AC Furnace Filters Number Per Box:6 With the 4" and 5"

With the 4" and 5" air filters there is a wider variance between the nominal and actual size depending on the manufacturer

Nordic Pure 20x25x5 Air Bear Replacement MERV 10 air filters measure an actual depth of 4 7/8"

Actual Size: 11 1/2 x 24 1/2 x 1/2 (11

Actual Size: 8 3/4 x 33 1/2 x 3/4 (8

Additionally

19x27x1 Exact MERV 13 AC Furnace Filters Number Per Box:6 With the 4" and 5"Actual Size: 19 x 27 x 3 4 (19 x 27 x 0. 75) Removes lint, household dust, pollen, smoke particles, dust mites, pet dander, virus carriers, mold spores, smog and other contaminants. Ideal for customers looking for superior filtration Hypoallergenic, antimicrobial, and electrostatic filter media. Moisture resistant frame. Nordic Pure MERV 13 is equivalent to MPR 2200 2400 Made in the USA. Nordic Pure MERV 13 Pleated AC Furnace Air Filters provide