I just recently got a Rockford Fosgate HE2 sub and a 400 watt jensen amp. I have a friend that is gonna build me a box. My question is What wiring would i need, Does the wiring come with the amp and sub or do i need tp purchase it serperatly. And if so what?

 

take the jensen back and get a real amp. Jensen is on par with Pyramid (AKA junk). I realize that you probably got it for a really good price, but it just doesn't stack up against good quality gear.

You will probably need to buy your own wiring stuff. With one amp you should most likely use 8gu. wire...