Top-Fill Design: Remove the lid to add cool water directly into the water tank, making refills and cleaning easier than the traditional humidifiers The 2-in-1 Humidifier & Diffuser: The Dual 100 acts as both a humidifier and a diffuser, so you can pair essential oils with the humidifier’s mist to spread your favourite fragrances throughout the room Intelligent Sleep Mode: Sleep Mode turns off all display lights and uses a built-in humidity sensor to automatically maintain a comfortable humidity level to let you sleep soundly; 1.8L provides ideal coverage for bedrooms, offices, baby rooms and other medium-sized rooms of 10-24 m² Whisper Quiet Operation & BPA Free: Sleep soundly as the near-silent ultrasonic cool mist technology generates less than 28 dB, which is quieter than a library. It’s also BPA free, which makes it perfect for your baby nursery Quality assurance: 3 Mist speed settings; automatically shut off when water runs out. Note: for greater effectiveness, please add essential oils to the base of the humidifier