in "Cold" by At The Gates, about... 2 minutes and 2 seconds into the song, there is this weird sound he makes on the guitar. if anybody is familiar with the song, and knows what im talking about can you give me a hand and let me know what the hell he is doing?

i been hearing in alot more songs, but cant think of any of the top of my head.
sounds like a flutter with a tremelo arm to me, should be able to find examples vids of how they are done on youtube