6 Pack of 18x20x1 MERV 13 Pleated Air Filters by Glasfloss. Actual Size: 17-1/2 x 19-1/2 x 7/8 ● Filtration Rating: MERV 13. Comparable to 3M/Filtrete MPR rating 1900 to 2200, or Honeywell FPR rating 10. ● Protects from pollen, dirt, dust, pet dander and virus carriers, smoke, smog, lead dust, oil smoke and micro allergens. ●
