Tier1 Replacement for Ultravation 16x25x5 Merv 11#91-005 AC Furnace Air Filter 2 Pack Captures 90% of harmful airborne particles such as dus, pollen, pet dander, mold spores, smog, & more Comparable Filter Replacement for various Ultravation systems that use 16x25x5 filters Actual Size: 15 5/8 inches (length) x 24 1/8 inches (width) x 4 7/8 inches (thickness) Original box type design Recommend filter life of 3 months to reduce damage to your furnace / ac unit