The Accumulair Platinum 20x22x1 air filter contains a unique synthetic media that provides high-efficiency filtration without comprising your airflow. The Tribo-Electric media is made up of co-polymer micro-fibers that are hydrophobic which means the filter does not absorb moisture and will not support the growth and spread of harmful contaminants. To increase durability the pleated media is laminated to a metal backing that is recyclable galvanized and corrosion-resistant. This filter is equipped with media tested to perform at the Minimum Efficiency Reporting Value of 11 (MERV 11) by an independent lab according to ASHRAE Standard 52.2. The high-performance filter captures up to 94% or more of airborne contaminants. All MERV data and statements are indicative of typical properties and characteristics obtainable. MERV claims are to be used as a guide for general comparison and not as a specification.