The Magpul FMG-9 is a prototype for a new generation of folding submachine guns, designed by Magpul Industries in 2008. Like other folding machine guns, it would be used for concealed carry and can be disguised as anything from a small package to an extra laptop battery. It is made out of a light-weight polymer material rather than metal, making it very light and easy to carry. It is also small enough even to fit in the back pocket of most everyday pants. It was developed for potential use by personal protection details such as the United States Secret Service. It is still a prototype and may or may not be made in large numbers for law enforcement agencies. The prototype uses Glock pistol firing mechanisms, specifically the 9mm Glock 17 pistol. It could be factory modified to fit a Glock 18 machine pistol for Class 3 or law enforcement use.