Honeywell Ultra Efficiency Filters

A genuine Honeywell Ultra Efficiency whole house air filter is up to 60 times more efficient at capturing bacteria, allergens, and other airborne particles than a typical one-inch fiberglass filter.

Whether you're looking for a 4" or a 5" filter, these are usually the correct filters for your system; measuring at precisely 4.375" they are designed to fit a wide range of furnaces. Ultra Efficiency filters carry a MERV 12 rating - they capture a very high percentage of air contaminants, including the smallest particles that are most harmful to your lungs.