Basic parameters: Power: 3W Voltage: AC22V/DC12V Applicable Area: 15-25 square metres Features:â_ 1.Instead of relying on fans to move air through filters, the machines release a steady stream of negatively charged ions to operate. So it woníªt produce any noise when in operation and is most suitable for use in bedroom. 2.It has automatic turn-off function and work circularly after a 20 minutesíª break. 3.The product produces 1.6í-1016 negative ions per second, and the negative ions are with the electrostatic field, the object with which can easily absorb the dust, one negative ion can capture one particle floating in the air. This is the reason why negative ion can purify air. Size: 270*145*110 mm