The "Reverse Bear Trap" used in this short film was made by an engineer friend of Leigh Whannell and James Wan. The device was not actually rusty as it had to be placed in Leigh's mouth. Also, it was completely working, but ultimately safe for obvious reasons. In the feature length film, Saw (2004), the device was also safe and coated with fake rust and Shawnee was holding the trap steady by biting down on wooden tongue depressors, not metal hooks from the trap.