A micro-bead or comm-bead is a short-range Vox radio wave communication device worn in the ear, good for communication out to about one kilometre (depending on weather conditions and intervening terrain). Each fits discretely in the ear, with master-crafted models nearly undetectable upon casual inspection. Micro-beads are used by most of the Imperial military forces, regardless of branch.
- Dark Heresy Core Rulebook (RPG), pg. 151
- Only War: Core Rulebook (RPG), pg. 202