* Big LED screen better display of oxygen concentration,flowrate,cumulative time,so that the elderly can see it more clearly. Anion generator can increase the air purity level,given freshness experiences as in nature. * Ultra silent,the unique denoise technique,running noise is less than 49dB,won’t disturb sleep while oxygenating. Real-time intelligent monitoring system to know the status of machine at any time. * Infrared remote control function within 5m,convention to control the machine.Detachable filter,convenient to replace or clean the filter. * The alarm function can ensure the user to clean the filter regularly for good maintaince to the machine.