It's a power outlet and yes many of us use them to charge cell phones etc. They are there for the ground crew to clean the plane. A problem with pax's using those outlets is that there is not one for everyone on board. By telling a pax sure go ahead and use it the guy behind will want to know where his is and so on. Also you will have people coming to the galley wanting to know if he/she can plug in and leave a computer in the galley to charge. It a can of worms most just don't want to open. I guess the best is just to ask first. I'll look it up in the manual and see what it says.