You have your POC-Inogen concentrator set on 'setting' 3.
That is not 3 liters of oxygen output ! That is just a number, a setting between 1-5. They never said that the numbers equal liters of oxygen, read the paperwork on your unit.

Your doctors office may have an in line flow meter to hook up to your hose and see what the liters it is outputting on setting 3. Usually about 2l.
An oxygen flow meter is that little glass vile on the front of your in home unit with the little ball you have to adjust to just above the 3 in order to get 3l of oxygen out of it. Then you are getting 3l of oxygen.
You can purchase an in line "oxygen gas liter flow meter" yourself if you need to. [They cost $32.99 by; Tinas home care, from Amazon.]

Wow Janice I just looked it up it cost 424 I have two small batteries I guess I’ll wait to buy one of them but thanks for information. I usually don’t go anywhere that long. I have a charger in the truck if it gets low.

I got a large double battery that lasts about 6 hours on liter 3 from amazon...worth the money

Dawn

See if you can get the extended battery and not the standard. It would really increase your ability to stay out longer and enjoy your day.

Thanks Michael. I will definitely order one. I’m probably ok on 2liter on my POC cuz I am usually on my scooter when I use it. I don’t exercise outside cuz of the weather. But I was using it in the shower on 4 and I changed to using my big machine while I’m in shower and I c a big difference the Ingeon battery doesn’t last long on 4. I just had to call Ingeon cuz my POC was working right and they sent me a new one. I have Medicare and Cigna for insurance and Cigna pays 100% for both the oxygen machines rentals. I very lucky I have good insurance.
Thanks again for information. Hope ur having a good day. I’m trying to send u warm weather but it’s raining here again today.