A killer mechanical contraption from the Saw movie franchise.
The trap was a mechanical contraption that was attached to its victim's head, and secured with a padlock. A timer was attached to the back of it. Usually, the victim had 60 seconds to find the key, unlock the trap and remove it. If the victim failed to do so the trap would burst open and rip their jaws apart, as the frontal part of the trap was hooked into the upper and the lower jaw. It was devised by the serial killer Jigsaw as a way of testing his victims' resolve, as the key was often planted somewhere either difficult or painful to reach.