Originally Posted by NWIFlyer

I use something similar, but a 10 way with a figure of eight lead. I typically use six of the ports. The 4 way version you have could pull up to 6.8A @ 5V. I'm not sure all plane sockets are rated to that (although we'd have to do an ac conversion to be sure, taking into account the efficiency of the power supply, so that's tricky!) - historically most were only designed to charge a phone or maintain battery levels on a laptop, which is nearer to 1A dc. So yes, you'd be fine charging a single device, maybe two, but I could see issues with fully loading the device.