23_3/4x23_3/4x1Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack plant-care/pest-&-disease-control and mildews off your plants

and mildews off your plants

Humidity Deadband:                              5%

Increases nutrient/water absorption

For amendment applications

23_3/4x23_3/4x1Exact MERV 13 Plus Carbon AC Furnace Filters 6 Pack plant-care/pest-&-disease-control and mildews off your plantsNordic Pure Custom MERV 13 Plus Carbon air filters are made based on the actual measurements so be sure to measure your current filter to get the EXACT dimensions before ordering. As with all Nordic Pure filters, the effective life of your filter depends on the environment in which you live. We recommend changing 1 and 2 filters every 30 90 days. Our 4, 5 and 6 inch thick filters could last up to 6 months. EXACT MEASUREMENT: Furnace and air condition