24x24x4 (3 5/8) Pleated MERV 15 Air Filters 1 Pack Grow System/ Trays/ Reservoirs The ES means Extra Strength

The ES means Extra Strength

Keep the container tightly sealed when not in use

Remember—keep your pH probe wet

Rugged and durable with waterproof connectors

The Bloom Booster you've been waiting for has finally arrived

24x24x4 (3 5/8) Pleated MERV 15 Air Filters 1 Pack Grow System/ Trays/ Reservoirs The ES means Extra StrengthNordic Pure 24x24x4 Pleated Air Filters MERV 15 are made of electrostatically charged synthetic materials that attract and capture most airborne particulates in your home. Each time air passes through a Nordic Pure pleated furnace filter, lint, household dust, pollen, dust mites, pet dander, smoke particles, smog, allergens, virus carriers, bacteria, mold spores and other contaminants are removed. All Nordic Pure pleated air filters are manufactured