Phresh Inline Carbon Filter — 6" (150mm)Phresh 6" (150mm) Inline Carbon Filter The Phresh Inline Filter solves a real problem most carbon filters have to sit at the start of your ducting chain, which eats up tent interior space. Phresh's inline design means the filter can live anywhere along the duct run, installed like an inline fan. Same trusted Phresh carbon, different form factor. Why growers choose the Phresh Inline 6": Inline installation sits mid duct, keeps your tent interior clear