Is this stomach fat or just loose skin?

I'm a 17 year old male, 6'1" and 156 pounds. My waist circumference is a little under 29 inches. I was wondering if this was loose skin on my stomach or just fat. Here are some pictures:
http://desmond.imageshack.us/Himg716/scaled.p hp?server=716&filename=imagewfa.jpg&r es=landing
http://desmond.imageshack.us/Himg600/scaled.p hp?server=600&filename=imageqbz.jpg&r es=landing
http://desmond.imageshack.us/Himg210/scaled.p hp?server=210&filename=imagekson.jpg& res=landing
http://desmond.imageshack.us/Himg864/scaled.p hp?server=864&filename=imagehaj.jpg&r es=landing

What do you guys think?

Fat.

Looks to be minimal, however.

Edit - I have an 8-pack, and I can still hold out my skin with some fat on it, sorta like your pics. Don't worry about a bit of fat, you need it.

certainly not loose skin or any amount of fat to worry about (or that I can even see).

i'm curious as to why you ask?

Original Post by mjsophia:

certainly not loose skin or any amount of fat to worry about (or that I can even see).

i'm curious as to why you ask?

I want abs

Original Post by patebishop:

Original Post by mjsophia:

certainly not loose skin or any amount of fat to worry about (or that I can even see).

i'm curious as to why you ask?

I want abs

You need to lift some weights and build more muscle then.

I agree, you need to build more muscle.  You look pretty skinny to me (can clearly see your ribs) and don't need to lose any more weight.  

Looking underweight to me! If you really want to have abs, stop concentrating on that bit you keep pulling out and start concentrating on eating healthy and muscle building exercise.

You can do it! :)