First of all thanks for the answer.If you do some surfing, you will see that 12V DC, 10 AWG is good for 15A to 15 feet of wire with 2% voltage drop. So, I'd say this is probably 10 AWG. Now, some of this is also dependent on the insulation type of the wire and that can affect the wire gauge.
The 10AWG is for 30 amps, seems to me a bit excessive for what I need.
I prefer the same factory AWG.