what size is the barrel connector on the AC adaptor for the 4-port usb hub and BC1.1 charger?

Is it a standard 2.1mmx5.5mm, or smaller?

Hi Vonn,

Thanks for posting your question here! The power adapter that comes with the Plugable USB2-HUB4BC outputs 2.5A at 5V through a center positive jack plug with outer diameter 4.7 mm, inner diameter 1.7 mm and length 9.5 mm.

Hope the above information helps! If you need any additional information, please do feel free to shoot us an email at support@plugable.com. We are here to help!