Lomi filters use activated charcoal to trap moist air, remove gases from circulation and reduce unpleasant smells - Lomi filters are a proprietary dual activated-charcoal filtration system. Lomi has 2 filter cages designed and placed in series to maximize the efficiency of filtration. - Odor Neutralized: To keep your kitchen smelling simply lovely, replace your Lomi filters every 3 months or 45 Lomi cycles - Each set contains carbon filters for 45 cycles.