Prop firearms generally fall into 3 categories. Blank firing guns are real guns in every sense of the word, as defined by the government, and are regulated and handled accordingly. As the name implies, they fire blanks – bullet shell casing with no projectile. Replica guns are props made with metal, resin, plastic, and/or rubber. Depending on the needs of the production and the scene, they can be made to look identical to real guns. They do not fire, have no firing pin, and are not subject to the same strict regulation and safety requirements as blank guns. Non-guns are similar to replica guns but have the added feature of an electronically-triggered muzzle flash to simulate a weapon firing.