The FBI is buying a 3D printer for research into improvised explosive devices (IEDs). In a notice posted last week, the FBI announced its intention to purchase a $19,000 Stratasys Objet24 3D printer, saying that the device would be used to “support the advanced technical exploitation of evolving and existing high technology explosive devices.” The announcement comes just over a year since 3D-printed gun inventor Cody Wilson fired his plastic pistol for the first time in May 2013 and subsequently uploaded the design files. In November 2013, the US Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) downloaded, printed, and tested the Liberator, as Wilson’s gun is known. Australian and German police are also known to have tested the gun. But while 3D-printed firearms have been well-debated, the potential threat posed by 3D-printed explosives is less understood.