M2m power options

Hi,

can someone clear this up for me I’m trying to work out how to power my m2m, the offical documentation reckons through the dc port but wikipedia reckons the usb-otg port as well based off the official documentation.

Also has anyone know where to get the correct size dc power plug, I’m not having much luck finding them

any help is appreciated pheonixfire

The dc power plug size is 4.0mm*1.7mm.