The Vox Caster is an Imperial radio communications transceiver that can be as small as a helmet mounted link and as large as a massive bank of dedicated communications equipment employed at an Imperial military force's headquarters. Usually a squad or platoon will have a link to their headquarters via one Vox unit and smaller relays for trooper to trooper communications. Command Units usually use more complex versions of vox casters known as Master Voxes. These pieces of communications technology can receive and transmit of multiple radio frequencies at once, making them ideal for coordinating the actions of multiple units at the same time. In absence of any form of Vox communications, troopers are taught to make use of sign language during battle.