Phat HEPA Intake Filter 4" HGC728790 and a wetting agent

and a wetting agent

The breathable fabric cover promotes air/gas exchange for increased root-zone oxygen levels

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GC refers to “Gentle Cut” as we appreciate and understand how delicate flowers are

17" internal diameter

Phat HEPA Intake Filter 4" HGC728790 and a wetting agentPhat HEPA Intake Filter, 4" The tightly woven synthetic HEPA fibers in this filter will help prevent mold, bacteria, pollen, insects and plant pests from entering your growroom or greenhouse. The HEPA fibers block out most airborne particles down to . 3 microns in diameter. That is 300 times smaller than the diameter of a human hair. This is a serious insurance filter, without it you are leaving your grow room susceptible to the elements.