As my subject now is a little accustomed to the vacuum plastic bag, I can dish out slowly tougher. He can create in an emergency a small cavity with his hands, but does it really avail him nothing. and it's fascinating to see through the clear plastic, the wide-open eyes of the ****** struggling for air and touch the heated face. Gave him at that moment, perhaps a bit more false sense of security ... warning: please do not copy alone. This could be dangerous!