Franklin Armory BFSIII CZ S1 Set off Procedure:Secure –Will not fire.Semi – Fires one round per pull.Binary – Fires one round on pull and 1 round on release.* Ambidextrous Security Selector.Will Fit most CZ Scorpion firearmsAmbidextrous Protection SelectorLaunch round is often canceled simply by transferring our Patented selector out of Binar