I think that the attachment of the attached coupler attached is the reverse. What you received is incomprehensible because black is + and white. It is easy to understand because black becomes - and white becomes + if it is reverse.
The cable itself is satisfied with the conductors firmly and so. I used it to connect with the solar panel, but I wanted to connect the MC4 connector side to the panel and the non-processing side to the charge controller, so I used the reverse color of the positive and negative. It was good if there was also a reverse of positive and negative as another version.