There are 3 female connectors on the backpack and 1 male. One of the female connections is on the outside of the backpack for fast access in case you are carrying a whole bunch of stuff inside the backpack. I found it much easier to charge the actual backpack and not have to take a battery out to charge it up and reinstall it. Having the external battery indicator makes it nice to know how much charge you have left. I really like that the backpack is waterproof because we tend to get stuck out in the rain but now I have no worries about it getting a little wet while we are at the zoo or other places we may have to walk out in the weather for a little while. There are several pockets inside the backpack that keep everything organized and ready to go. No more digging around looking for your devices and other things when there are so many pockets to put everything. I was really impressed how the backpack feels, it isn't a rough nylon it is very soft but still very durable since we packed it full for this last trip. I would recommend this backpack to anyone that is on the go, or just needs extra charging ports while they are on the road.
Where to purchase: Amazon