Battery bank

I am using an Anker 1000m as a back up battery for a ver 2 and Pan cam that are daisy chained together. It works pretty well but would like swap it put for a a battery bank that has 2 USB outputs so the cameras are not daisy changed. The one I am looking at has 2 USB outputs, but 1 of them is a rapid charger. What is the max input maps the cameras can handle? And has anyone tested to see how long 20,000 mph battery banks will keep them running when power goes out?

It will rapid charge only compatible devices, so, as long it’s USB it’s fine, since the camera will only power draw what it needs. Original charger is 1A so that’s the recommended minimum, ( it probably doesn’t need that much)