What could it be?

I'm a little stuck on a sound. I'm trying to figure out how to get that like high pitched bend sound on the lower strings. Pinch harmonic keeps popping in my head but I don't think thats what it is. An example: http://www.soundclick.com/bands/0/therottenguitarstringmusic.htm
thats cw14's site. click on master of puppets, and about at the 51-52 second mark you can hear it. How do I play this?

are you talking about artificial harmonics?

That would be a pinch harmonic. From my experience with pinch harmonics a lot of things will depend on the sound of it as well as the tuning. A downtuned guitar will get a much more eerie pinch on lower strings and higher strings will get you a higher pinch. that one (not sure so don't hold me to it) might've been done on the D or G strings. Also, I've noticed that where you pick on the strings will also change the timbre of the harmonic. for example. My stratocaster has 3 single coil pickups. If I pick closer to the neck pickup I tend to get a deeper sound (for lack of better say) where it seems to be higher if I pick closer to the bridge pickup. The action also has some part in this. My SG's action is higher than my Fender and gets far better pinches. Same factor applies to the SG though it only has 2 humbuckers. If I aim closer to the bridge pickup then I'll land a deeper tone. Also, there are most likely some weak spots that don't get much of a sound out of pinches. Kind of dead zones vs the hot spots that get you a good sound. Also, pinches take time to get right, they're not the easiest thing in the world and mimicing the same tone twice is equally challenging. Just stick with it and keep a close eye on your picking hand. Oh yeah. One more thing. Bends and vibrato will also alter the sound a bit too as well as sliding and any other technique you can think of.

oops, i get so mixed up with the harmonics, wait, so, pinch is where you lightly hit it with your figner and it makes the high sound? then whats artificial harmonics?

A pinch harmonic is a type of artificial harmonic. And I was right about the D string (sort of).

I don't use pinch harmonics very often, but I can do them whenever. Its very hard to explain what you physically do, but you kind of pick, and hit the top of your finger nail on the string at the same time. Just experiment with that, and you will figure out how to do it. Once you got it, you got it, because like I said, I don't do it often, but if I want to, I can always do it.