Our Stratus filter is has MERV 8 filtering strength. This the best overall filter strength for both residential and commercial. The Stratus is “Made in America”. These filters are comparable to the highest quality filters at your local hardware store, but these are delivered to your door at the frequency you request (1-month, 2-month, 3-month, 4-month, or 6-month intervals). Let us take the worry of changing your filters for you. We save you time, money and headaches by “remembering so you don’t have to.” If you do not see the air filter size you need click here or let us know the size you need.