TruSens Air Purifier Carbon Layer (Assorted Sizes)REMOVE ODORS, GASES, DUST + PET HAIR: Filter replacement is essential for your air purifier to perform at its best. The activated carbon layer removes certain gases and odors from the air.LASTS UP TO 3 MONTHS: For best results, replace carbon layer filter in your TruSens Air Purifier every 3-4 months. Carbon layer filers are not washable so have replacements on hand to keep your home clean, fresh, and pure.SIMPLE INDICATOR LIGHT: Our design and simple touch controls were created with you in mind. A clear change indicator light is displayed on the purifier when the filter needs to be replaced, so you don’t have to play any guessing games.TRUSENS COMPATIBLE: Our simple, easy to use TruSens filters are designed for you and your lifestyle. The medium DuPont Replacement Carbon Filter is only compatible with the Z-2000 TruSens Standard HEPA Filter and Z-2000 TruSens Air Purifier.