Adjustable oxy-gen concentration: supply continuous flow 1-6L/min adjustable, 30%-90%,(1L: 90%±3 2L: 50%±3 6L: 30%±3 ) Portable and lightweight: only 5.2kg, Could work plug-in home power supply(AC 110V )for continuous working 24 hours a day if you do not set timer. Intelligent Control: IMD beautiful large color panel, easy to operate, large color LED screen, el-ear display, timer operation function and with infrared remote control, let it be easier and more convenient. Anion :This machine is equipped with ion function, and a &quot ;negative & amp;amp ;quot; button; the negative ion system can work alone , you can also work simultaneously with the oxygen system ;Anion generator Air vents located in the machine, the exhaust vents discharged into the surrounding space of the machine when working. Multi-layer filter, self-easy to replace: The oxygen system of this product has coarse dust filter, fine dust filter and three bacterial filtration treatment for the input air respectively, finally, the oxygen is fresh and clean after filtering , and the two front layers filter can be replaced without disassembling, the user operate it comfortably.