CC - 4142 CC - 4142 , nicknamed " Lock , " was a clone trooper captain serving under Jedi Master Eeth Koth in Horn Company during the Clone Wars . In 21 BBY , Koth ' s " Venator " - class Star Destroyer , the " Steadfast " — with Lock on board — was attacked near the Arda system by Confederate forces led by General Grievous aboard his Separatist destroyer . During the ensuing engagement , Captain Lock and some of his troops assumed defensive positions at one of the Star Destroyer ' s airlocks shortly before B2 super battle droids used an armored docking tube to board the Star Destroyer . As Lock and his clone troopers fought the intruders , Koth contacted Lock from the bridge , asking for a status report . When Lock reported to him that they were being overrun , the Jedi Master ordered the captain and his men to board the ship ' s escape pods , and Lock obeyed . Biography . Like all clone troopers , clone trooper captain CC - 4142 , nicknamed " Lock , " was a clone of the Mandalorian bounty hunter Jango Fett born on the planet Kamino to serve in the Grand Army of the Republic during the Clone Wars . In 21 BBY , the second year of the war , Lock served under Jedi Master Eeth Koth in Horn Company on board the " Steadfast " , a " Venator " - class Star Destroyer on a mission to hunt down Separatist agents . During a patrol deep in the Outer Rim Territories , near the Arda system , Koth ' s " Venator " - class Star Destroyer came under attack by a fleet — consisting of three " Munificent " - class star frigates and a Separatist destroyer — under the command of General Grievous , the Supreme Commander of the Separatist Droid Army . After a short exchange of broadside fire , Grievous ' s destroyer forced Koth ' s warship into submission , and the Separatist troops prepared to board the Republic vessel . To counter the enemy attack , Lock and his troops assumed defensive positions at one of the ship ' s airlocks . B2 super battle droids then used an armored docking tube to board and storm the cruiser . A firefight ensued between the battle droids and Lock ' s men , and during the skirmish , the captain was contacted by Koth , who was on the cruiser ' s bridge . Koth demanded a status report , and Lock reported that they couldn ' t hold their position any longer . The Zabrak Jedi Master then ordered the troopers to the escape pods and stated his intention to deal with Grievous on the bridge . The captain objected to this course of action , warning Koth of the advancing commando droids before obeying . Personality and traits . Lock showed visible concern for Koth and objected when the Jedi Master expressed his intention to engage Grievous separately on the bridge of the Star Destroyer . Although Lock and his troops valiantly tried to stop the droids ' advance , they were unable to prevent the super battle droids from boarding the ship . Like his clone imprint , Jango Fett , Lock stood 1 . 83 meters tall . Equipment . In combat , Lock used a DC - 15S , wore Phase I clone trooper armor with green markings , and he had equipped his helmet with a visor . Behind the scenes . Lock first appeared in " Grievous Intrigue , " an episode of the of , which aired on January 1 , 2010 . Although he was not named in the episode , he received a name in its corresponding episode guide . Lock was voiced by Dee Bradley Baker , who portrays all clone troopers in the series . Lock received the designation " CC - 4142 " in " " .