Does anyone know for sure what the size of the DC plug size is for the Ecotech Battery Connector slot on the controllers is? I'm having the hardest time finding this information. I'm setting up a battery backup and will be creating 25ft cables to run from my basement but can't seem to find the correct size. It seems way too small to be a 2.1mm x 5.5mm. I'm hooking up 2x Vortechs and 1x Vectra M2.