17_1/2x17_1/2x1 Exact MERV 7 Plus Carbon AC Furnace Filters 6 Pack commercial-lighting-fixtures With a maximum water holding

With a maximum water holding capacity of 60% there is no need to add perlite

be sure to monitor PPM and pH after adding

The Plant Strapper will save you time and effort in the garden

- Includes 8 foot pre-wired 120V cord

17_1/2x17_1/2x1 Exact MERV 7 Plus Carbon AC Furnace Filters 6 Pack commercial-lighting-fixtures With a maximum water holdingNordic Pure Custom MERV 7 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