The chip scanner was a device built by the rogue former clone commando Tech shortly after the formation of the Galactic Empire, intended to monitor the function of the inhibitor chips that clone troopers were implanted with. Although most of the members of his squad, Clone Force 99, were immune to the brainwashing command of Order 66 which was used to activate the chips and turn the rest of the clone army against their Jedi leaders, Tech wanted to ascertain whether their chips were truly defective.
Tech was forced to put off constructing the device when the squad's shuttle, the Marauder, crash-landed on the Ordo Moon due to damage it had sustained in a firefight. Coming to believe that the chips were no threat to the remaining members of the Bad Batch, Tech did not finish the scanner until the squad was reunited with their friend and fellow rogue clone Captain Rex, who was incredulous that they had not removed their chips due to the danger they posed. The Batch subsequently rendezvoused with Rex on Bracca to remove their chips, and Tech finished the scanner en route.