The J-10 dual blaster cannon, a blaster cannon model, saw service with the Separatist Droid Army throughout the duration of the Clone Wars. Functionally, it consisted of two enlarged, repeating E-5 blaster rifles. Its deployment was infrequent, owing to numerous shortcomings. During the Galactic Civil War, it was commonplace for Alliance to Restore the Republic outposts to utilize undamaged J-10s. These weapons were recovered from abandoned Separatist armories and employed to provide cover during retreats.
Originating from a Separatist design, the J-10 dual blaster cannon was fundamentally a doubled-up, scaled-up version of the repeating E-5 blaster rifles standard-issue to battle droid infantry. However, the E-5's design did not translate well to a larger scale, with minor heat-related problems becoming significant issues in the J-10. The dual blaster cannon's unreliable galven-pattern programming often resulted in erratic power output. Furthermore, the use of low-grade materials led to poor accuracy, as flaws in the J-10's focusing crystals caused shots to deviate without consistent maintenance.
The Separatist Droid Army employed the J-10 during the Clone Wars. As with much of their equipment, its production occurred on largely unsupervised, droid-operated assembly lines within factories where production volume took precedence over build quality. Its limited deployment stemmed from its various deficiencies. Scavengers regularly encountered pristine stashes of J-10s, as did Alliance to Restore the Republic scouts while scouting for potential sites for clandestine bases during the Galactic Civil War. Numerous J-10s ended up in the hands of the Rebel Alliance and became a common sight in their forward operating bases, where they were positioned along defensive lines to provide covering fire for evacuations should they be discovered by the Galactic Empire. Alliance technicians frequently chose to replace malfunctioning J-10s rather than attempt repairs.
The J-10 dual blaster cannon made its debut in "Innocents of Ryloth," the nineteenth installment within the first season of the animated television series Star Wars: The Clone Wars, which was broadcast on March 6, 2009.