Good equipment.
Unit supplies oxygen on demand.
One has to remember to breath through the nose. If a sleep and one suddenly starts breathing through the mouth the alarm will go off (No demand for some time). This will wake you up and your partner if in the room. Switching the alarm off one has to open the plastic protection lid and press the numbered button twice to reset. Not easy and quick when very sleepy.
Noise level is acceptable.
Power transformer is somewhat under rated, when the power gets warm/hot it does not function fully and the unit switches to battery mode, i.e. one starts draining the battery while still on power supply. (Room for improvement)
Unit works well in airplane (I had power supply) but as mentioned with the alarm, other passengers and service staff can get nervous.
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