Stadler Form Robert Washer Purifier Portable humidifier with air Cleaning Properties, Black Four speed levels and three automated modes for ease of use: night- mode, clean-mode, and auto-mode Remove and separate the discs from within the Robert and hand wash or add to the top row of your dishwasher for easy cleaning Robert efficiently humidifies a space up to 860 square feet in size using a digital hygrostat, and will automatically shut off when the 1.7-gallon water tank is empty You may choose to stimulate your senses or calm your nerves with a few drops of your favorite pure essential oil (no synthetic oil, please) placed on Robert's integrated fragrance dispenser Suitable Accessories: Water Cube, Anticalc Cartridge, Zero Calc, or Stadler Form Pure Essential Oils