A magna-coil used to attract swarm mines
The magna-coil was a magnetic component integrated into the R-series astromech droid [QT-KT]'s(/article/qt-kt) dome. During the period of 20 to 19 BBY, her magna-coil was utilized by QT-KT to pull in numerous swarm mines. This action was part of D-Squad's mission to retrieve a Separatist encryption module from the flagship commanded by the tactical droid Aut-O. The mines, drawn in by the magna-coil, were then securely stored inside her dome. Subsequently, both the magna-coil and the swarm mines were ejected from her dome, resulting in the destruction of several battle droids.
The first appearance of a magna-coil, though not explicitly named, occurred in "Secret Weapons," the tenth installment of Star Wars: The Clone Wars' fifth season. This episode was initially broadcast on December 1, 2012. The name "magna-coil" was officially used in the episode gallery accompanying the episode on StarWars.com.