Purifier Big+Quiet Formaldehyde BP04 (Prussian Blue/Gold)Our quietest, most powerful and advanced air purifier. With exclusive K carbon filter. CO sensing. Captures 3x more NO, a common urban pollutant. And cools you. 50% quieter, even at full power Acoustically engineered to produce less noise. Night mode is 50% quieter than any other Dyson purifier. With a Sleep timer so you can set it and forget it. Powerful projection to cool you down Delivers over 21 gallons of purified air per second. Adjust the angle