Carbon filters are no longer just for the ends of your air filtration system. Now they can be installed in-line like the lights and fans. It is the same Phresh? Carbon Filter users' trust, built into an air conserving body. Point to point air movement and filtration. Phresh Inline Filters are state of the art carbon filters that practically scour the air to clean it of dust, foreign particulates, organic compounds and odors. Phresh Inline Filters are twice as light and last twice as long. Phresh? In-Line Filters are perfect for the following applications: Grow tents, cupboards and cabinets. Anywhere without a roof/ceiling cavity to displace extracted air into. Air-cooled lighting. Lower-level floors of double/triple story houses. Window to window ventilation applications. Hot or cold filtered air transfer from one air conditioned room to another.