Haha it's like this little tube that's attached to a pedal that allows the guitarist to shape the note he's playing with his mouth. Bon Jovi uses it a lot
I like them and there really good live...though for some stupid reason me and my sister left before the were done:angry: [we had went there to see Three Days Grace manly...but Nickelback were probably the best]........I want one of there cd's but I hve no money and when I do I tend to use it for something else.....