Detroit police commander Ryan Connor calls it a “nightmare.” It’s a quarter-size gadget that turns Glock handguns into machine guns, firing multiple rounds with a single trigger pull. “You get the mindset of people with these types of weapons that they are going to inflict as much damage and hurt as many people as they can, quickly,” he said. “And that’s why it’s so disturbing.”

Across the country, similar devices called glock switch have popped up at crime scenes. They are made by third parties and can be plugged into the back of certain semiautomatic pistols to allow them to fire continuously, as if they were fully automatic weapons. The small device interferes with the gun’s internal mechanisms to allow it to fire at up to 1,200 rounds per minute.

Police recovered a handful of them from crime scenes in 2012, but between 2021 and 2023, the number rose 784 percent to 5,454 — with criminals getting their hands on them more often. Law enforcement officials say the devices are easy to find and easy to use, thanks to online videos that guide people through the process.

Glock switches can lead to serious legal consequences

Possessing a switch without the proper legal permissions is illegal, and can carry significant prison time and hefty fines. And because it is considered a weapon conversion device, a person convicted of that charge will lose the right to own any firearms in the future. Several cities and states are taking legal action against the manufacturer, Glock, accusing it of failing to prevent such illegal modifications. But the company says it cannot redesign its pistols to make it harder to attach the switch.