When I installed the Pioneer AVIC-X950BH head unit, the speaker wires from the unit's harness were soldered and shrink wrapped to the LAN adapter and the LAN adapter was soldered and shrink wrapped to the car's speaker wires. I did not use any RCA plugs and the owner of the shop I dealt with said that is a much better way to hook up the speakers as RCA plugs go bad after a while from corrosion and dust and dirt.