WHAT IT IS A design icon. The Stone Diffuser scents the home and looks beautiful while doing it. With a matte ceramic cover and sculptural silhouette, it doubles as a piece of décor. Ceramic cover 4-hour & 8-hour run times 500 sq. ft. diffusing capacity 46.4 oz Imported HOW TO USE IT Fill the water reservoir to the fill line. Add 20-30 drops of 100% pure essential oils. Put the plastic cap and then the ceramic cover back on. Select a time setting. Cosmetics - Wellness > Vitruvi > Saks Fifth Avenue > Barneys. Vitruvi. Color: Charcoal.