24" x 28" x 4" MERV 13 - Ultimate Allergen Reducing Pleated Air Filter - 6 Pack MERV 13 - Pleated Air Filter:24" x 28" x 4" MERV 13 - Pleated Air Filter They help capture airborne particles/allergens

They help capture airborne particles/allergens between 3-10 microns in size and are an ideal upgrade from standard disposable panel filters

18" x 25" x 2" MERV 13 - Pleated Air Filter - 6 Pack

Instead of face loading (particles captured on the outer surface of the filter) the filter uses stage loading

Actual Dimensions: 19 7/8" x 31 7/8" x 3/4"

21 3/8" x 21 5/8" x 1" MERV 8 - Premium Pleated Air Filter - 6 Pack

24" x 28" x 4" MERV 13 - Ultimate Allergen Reducing Pleated Air Filter - 6 Pack MERV 13 - Pleated Air Filter:24" x 28" x 4" MERV 13 - Pleated Air Filter They help capture airborne particles/allergens24" x 28" x 4" MERV 13 Pleated Air Filter 6 Pack Actual Dimensions: 23 7 8" x 27 7 8" x 3 3 4" Filtration Group's High Capacity MERV 13 air filter is made of 100% Synthetic Media which will not promote mold or bacteria growth and has the following features: MERV 13 Efficiency, LEED compliant, High Efficiency in 2" depth, Advanced media incorporating both charged fibers and traditional mechanical principles, 100% recycled paperboard frame, Easy