Natural. PURE SOURCE INDIA ULTRASONIC HUMIDIFIER AROMA DIFFUSER: The finest quality ultrasonic humidifier aroma diffuser with advanced technology and features. Provides excellent performance when used in dining, bathroom, bedroom, office lounge area and any other medium-sized place. LATEST ULTRASONIC TECHNOLOGY:Advanced Ultrasonic Humidifier Aroma Diffuser with latest technology that produces vibrations at a frequency of 2.4 million times per second to break water and essential oils into very tiny micro-particles without using heat for ease in reaching every corner of the interiors. TECHNICALLY ADVANCED UNIT: 400 ml water tank capacity that can continue to operate for 9 TO 15 hours in each refill. There is also an auto power off at the time whenever the water runs out. Press the mist button and enjoy the soothing aroma for a relaxed feel. Just feel the tank with normal drinking water about 80 % than put 4/5 drop of oil in the water per / 100 ML ,Switch it on ,Immediately it's start working , now you enjoy this product decoration , fragrances and quality of work according to your own comfort . You may just use add there 5 or 6 drop of Lemon In the normal water , that lemon mostly every one use in Kitchen , just feel the natural essence of the same , IDEAL FOR ALL INTERIOR SPACES: Perfect choice for small to medium spaces including dining, bedroom, bathroom, office, cubicles or lounge area. Must have solution for areas where air conditioners are used frequently to prevent drying of air by keeping the balanced moisture level within the interiors.