Suppressor

Suppressor
A suppressor is a device that is fitted to a weapon to silence the sound of the gun fire.

On the episode "Thor's Chariot" we see O'Neill and Teal'c fit suppressors onto the end of an MP5 and Teal'c, on his M9 pistol, to take out the guards around Heru'ur.

On the episode "Smoke and Mirrors" Agent Mark Devlin who is disguised as Major Paul Davis attach a suppressor to his weapon to kill Senator Kinsey, both on the Remington Model 700 and on the pistol.