A micro-transporter is a device that allows an individual to transport small objects. In 2375, Chu'lak attached a micro-transporter to a TR-116 rifle. Using a targeting sensor he began killing crewmembers on Deep Space 9 by firing the weapon, which beamed the bullet into the room the intended target was in. The bullet would then continue its course. Miles O'Brien later added a micro-transporter to a TR-116 riflle, which Ezri Dax used to stop Chu'lak. (DS9 episode: "Field of Fire")
In 2379, the crew of the USS Enterprise attached micro-transporters to their TR-116 rifles when they were fighting against rebel Tezwans during their peacekeeping duties on Tezwa. (TNG novel: A Time to Heal)