Joe made his Lulz Liberator from PA-747 ABS plastic, a standard kind of ABS that is the working material for most consumer-grade 3-D printers. Yet he claims that it's stronger than the more expensive stuff Wilson prints with in his larger, more costly Stratasys printer. Joe also augmented his version with a few components not found on the original Liberator, which is all plastic except for the firing pin made from a standard nail. The Lulz Liberator uses a metal nail for a firing pin, but also employs metal screws--available for pennies at your local hardware store--to hold the body of the firearm together rather than relying on plastic pins as Wilson's does. And like Wilson's, it contains a non-functioning piece of steel designed to bring it into alignment with the Undetectable Firearms Act.