14x18x1 Exact MERV 13 AC Furnace Filters 6 Pack Growing Accessories hydrate and calibrate pH probes

hydrate and calibrate pH probes as well as clean and test conductivity (ppm/EC) probes

flow restrictor

Precisely control photon output when paired with Autopilot PX series controller (PX2 and above)

Only lightly charged with organic nutrients

14x18x1 Exact MERV 13 AC Furnace Filters 6 Pack Growing Accessories hydrate and calibrate pH probesNordic Pure MERV 13 Pleated AC Furnace Air Filters provide exceptional filtration for both home and commercial environments. Each time air passes through a Nordic Pure pleated furnace air filter, lint, dust, pollen, bacteria, pet dander, dust mites, mold spores, smoke particles, virus carriers, coughs and sneezes, smog, allergens and other contaminants are removed. MERV 13 furnace filters are comparable to HVAC filters with the rating of MPR 2200