Saw is an Australian nine-and-a-half-minute Short subject Horror film by directors James Wan and Leigh Whannell. It was created from a scene they chose from the script for Saw (2004). It was originally used to pitch their script to various studios and actors. On the internet it has often been referred to as "Saw 0.5".
This short film later became a scene in the feature film Saw, with Amanda Young wearing the Reverse Bear Trap device instead of David.sawfilms.wikia.com/wiki/Saw(short_film)