The BS-1 Tishina is a silencedRussian 30mm grenade launcher. It is developed specifically for the AKS-74Ucarbine. It uses a bolt-action mechanism to load blanks into the chamber along with the 30mm grenade. Pulling the trigger ignites the blank which in turn ignites the charge on the grenade causing the grenade to be expelled from the barrel. The "tishina" name was given to it because of the fact that it is silenced(Tishina means silence in Russian) grenade launcher.