I take care of my 90 year old mother that is on oxygen.

I looked into a portable unit but they are very, very expensive.
I asked the oxygen co. about one and they told me Medicare will provide a portable unit OR Tanks but not both. I am not comfortable being out with a unit that may stop working with no back-up.

Seems to me for advances in electronics we have now days Oxygen machines are so primitive. Why someone on oxygen has to get up and walk to their machine to turn it up or down. Why not have a wireless remote available, Its even hard for me in my 50's to see what number its on let alone someone in their 90's. A small LED to light up the display would be very helpful.