This air purifier works to target odour at the source, decreasing dust and removing odour. It uses infrared thermal system technology to sensitively and accurately identify when your pet enters the detection range. For 60 seconds following detection, the negative ion generator within the air releases high-activity negative ions to deactivate bacteria. The negative ions work by absorbing dust and inhibiting bacteria growth, this decrease in dust purifies the air. Each air is equipped with five odour removal air ducts at different tilt angles to ensure maximum coverage. The high polymer solid air freshener extracted from 20 pure plants is safe and non-toxic, it can remove odour and refresh air as well as decompose the odour molecules such as nitrogen and hydrogen sulphide, etc. Also, it helps to promptly suppress the decay of micro-organisms contained in odours and prevent bacteria growth. It removes odour automatically when pets enter the detection range; as well as running every 6 hours automatically to help promote fresh air all day & night.