Solar panels do have two cables on the back with connector coming out of a rectangular box . Those cables should be connected to the orther panels and the inverter.
Nobutec only uses first class cables form Solinq. Special cables for solar panels in three different colours. Adapted to all weather conditions and specially UV-protected, because the sun is burning day in, day out.
But not only the cabling comes from Solinq, also the plugs. The connectors are coverd with a thin silver layer for a better electricity-flow and so have a very low resistance. The connectors are clicked together, completely watertight, for a secure connection.