metra wire harness for 2009 honda accord

I have this https://metradealer.com/api/vfg/view-product/id/70-1730 to integrate my factory amp into my Pioneer avh-p4200. I have no clue what those RCA's are for or what they connect into. Anybody know? If I can't figure it out I have a normal harness for my car to use.

White - Left Front

Gray - Right FrontGreen - Left RearViolet - Right Rear

MECP Basic Installation Tech

Certification ID: CEA195600

Pioneer AVIC-X920BT

Polk Audio DXi 6500 - front

Rockford Fosgate Power T1693 - rear

Alpine MRP-F300

Alpine MRP-M500

Alpine SWR-1242D

What does this connect to? I assume it's for the little 8" driver (the 7th speaker).

Yep... that would most likely be for the factory sub in there. Do you not have a car side harness that it can plug into? And then of course it would plug into the aftermarket radio into one of the sub inputs. I'd advise getting a Y-adapter RCA so that you can hit both Left and Right channels.MECP Basic Installation Tech

Certification ID: CEA195600

Pioneer AVIC-X920BT

Polk Audio DXi 6500 - front

Rockford Fosgate Power T1693 - rear

Alpine MRP-F300

Alpine MRP-M500

Alpine SWR-1242D

Yeah I found the factory harness to plug it into and put it into the white sub output on the head unit. Its just temporary until I replace my blown 12" though so I won't concern myself with the y adapter. Thanks for all the help guys. Appreciate it! It's all hooked up and running properly. Only thing is the iPod crackle sometimes on the Avh-p4200, but nothing else crackles.