Developed by CETME in the 1960s, the C2 (aka CB64) submachine gun was clearly inspired by the Sterling, but includes several clever mechanical safeties. The charging handle is non-reciprocating and integrates a bolt lock which it automatically deactivated when the charging handle is used. This allows a loaded magazine to be safely carried with the bolt forward on an empty chamber. It also has a bolt block that is retracted when the trigger is pulled, which will stop the bolt from fully closing if the gun is jarred or the charging handle snagged. Finally, it has a retracting spring loaded firing pin that does not come forward until the bolt is fully forward, thus preventing out of battery detonations. Made in both 9mm Parabellum and 9mm Largo, it is a clever and well designed submachine gun, only let down by an uncomfortable folding stock.