16x20x4 (3 5/8) Furnace Air Filters MERV 8 Pleated Plus Carbon 2 Pack Air Purification Designed to prevent equipment with

Designed to prevent equipment with counter active functions from operating at the same time

BNC universal connector

This product provides excellent support for plants and makes harvesting a breeze

This promotes healthy root growth and builds robust plants from the root up

Biologically

16x20x4 (3 5/8) Furnace Air Filters MERV 8 Pleated Plus Carbon 2 Pack Air Purification Designed to prevent equipment withImportant Note: Almost ALL furnace filters have a different "actual size" than the nominal size printed on the air conditioner filter. It's best if you measure your air filter for the EXACT size and compare it to our "Actual Size" and then you can be sure your A C air filter fits! With the 4" and 5" air filters there is a wider variance between the nominal and actual size depending on the manufacturer. If you are replacing a 4 3 8 depth 16x20x4 filter