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I don't know what kind of battery operated air pump I have because there was only one to chose from at the LFS I have used it when moving and it worked well. I have never lost power long enough to use my air pumps at home.
I have two of the Hagen battery powered air pumps. They are LOUD and fit together like crap. The D batteries have a tendency to pop out once you try to put them in as well. I would never buy another one. Unfortunately I bought of them at the same time
The PennPlax pumps look pretty nice. They plug into the wall and when a power loss occurs, they automatically turn on and use the battery power.
We have an Azzo double "nonstop" model.
It has an option for intervals, which helps save its 2 hour battery life aand make it 3-4 hours. It is also very quiet (i really like that in a pump!)