The Knife used by Tyler Mane (Michael Myers) throughout the film.  COA from Rob Zombie

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This is one of only two knives from production to be officially released with a COA from Rob Zombie.  This exact same style knife can be seen throughout the film being used by both Daeg Faerch and Tyler Mane as Michael Myers.  This particular knife has a blood tube in the back for a "blood spitting" effect and was used specifically for the stabbing scenes throughout the film.