Neural-Inhibitor Collars are thick bands of metal that, when placed around the neck, stop any neural signals that aren't necessary for continuation of life, utterly paralyzing the subject. The UNSC tried them for capture of dangerous felons but the technology was put aside for unknown reasons, though it was most likely due to safety concerns. General Howard Graves used them when he tried to capture the SPARTAN-II unit Blue Team during the Raid on Camp New Hope.