I am (trying to) building this:

https://www.youtube.com/watch?v=WFLYIlCwE6w&

I bought the MC4 Y adapters on accident (or at least to join panels together) and need to buy the adapter cord below. Which ones do I get?

https://www.amazon.com/Renogy-Controller-Connector-Adaptor-Extension/dp/B00DGXGKWA