itd use 12-14 nothing really bigger cause itll most likely get in the way of other wires when ur running it throughout the car. anything thicker would be a waste i think. remote wire runs to the back or whereever ur amp is gonna be. doesnt really matter on its thickness but itd use the same shit just to make it look more uniform. then just run a tinnier piece of wire from one amp to the other remote on the other amp. set to go.