Board Thread:Questions and Answers/@comment-35433984-20180504173547/@comment-31642261-20180505202141

Click on the gun you want to silence in the inventory, and press 'Modify Weapon'. This will bring you to the attatchment menu, where you can find the 'Long Supressor', currently the only silencer in the game. Equip it, and your gun should be silenced. Now you can shoot that gun in stealth and nobody will hear it!