The C1-series astromech droid represents a specific model within the C-series line of astromech droids, which were produced by Industrial Automaton. These droids saw action throughout the Clone Wars era and continued to be utilized during the time of the Galactic Empire; however, by the Imperial period, they were viewed as outdated, having exceeded their intended lifespan by several decades according to the manufacturer. A defining characteristic was their possession of three articulated mechanical arms for object manipulation, along with an integrated electrical arc welder. An example is CH-33P, also known as "Cheep," who was stationed aboard the _Venator_-class Star Destroyer Tribunal during the events of Order 66. Cheep played a role in Ahsoka Tano's apprehension of Commander Rex and later aided their joint escape from the vessel before meeting his demise at the hands of clone troopers. Another example is C1-10P, a droid nicknamed "Chopper," who served on the [Ghost]. He was a C1 unit, although his appearance was inconsistent due to numerous repairs and modifications over time.