Buyers beware: The actual size of the 16x20x4 was reduced at some point last couple of years. As the result it doesn't properly fit in Honeywell / Lennox filter boxes, despite the advertisement on the packaging. The filter size used to be 15-7/8" x 19-7/8" x 4-5/16". The new filter size is 15-7/16" x 19-3/4" x 4-5/16", so it is 7/16" (1 cm) narrower than the old filter.

Yay !! Delivery was earlier than expected.

Great product and filter for your money. I will definitely buy again

Love the dirt that these collect. It’s amazing.

Best filter available for severe allergies

Good filters. Good price.

filtrete 16x25x4 furnace filter

I love these filters. Once a year and you are done. Sams club had them at an affordable cost.

These are the best of its class when it comes to 4 inch filters, and he most reasonably priced

Does an excellent job of collecting dust. However, depending on your environment, don't expect more than a 60 to 90 day life.