Serene House Astro Additional Colors A gradient dark color of outer case symbolized the sky dome during nights, glowing color changing as if the luster from distant star cluster. Atomization Mode: Ultrasound Continuous Atomization Time: Approx. ≥ 4 hrs Suggested Room Size: 10 - 15m² (107.6 - 161.4sq ft) Water Tank Capacity: 90ml (3.04 fl . oz.) Product Size: L 9 cm x W 9 cm x H 15.5 cm ( L 3 ½ in x W 3 ½ in x H 6 ⅛ in )