Havent you ever seen the movie Saving Private Ryan, where the one dude has the sticky grenade/bomb and runs up to the tank and explodes before he can put it on it? yeah thats what they are, they used basically C4, put it in a sock and used some sort of sticky agent, some glue or something it was like brown i think...then they would put it on the tank tracks to disable the tanks...it worked effectively...

it was axel grease

yea i saw that that was fuckin awesome!