TRIGGER OPERATION: Position 1 Safe Will not fire Position 2 Semi Fires 1 round per pull Position 3 Binary Fires 1 round on pull and 1 round on release FEATURES: * Release round can be canceled by simply moving our Patent Pending selector out of Binary mode while holding the trigger back * Works in most 9mm and .40 Cal Ruger PC Carbine trigger housings * Great for competition shooters, tactical shooters, and recreational enthusiasts * Gunsmith Installation Recommended