V series? Lol btfo
(media.scored.co)
The 'glock switch', a device that can be added to Glock handguns, turns them into machine pistols. They're illegal, but are very commonly acquired and are easy to install. As AnotherAlt said, Glock was pressured to discontinue older models and introduce a new one with a fire control that is incompatible with existing switches. It didn't take long to figure out a workaround.