Graph 18
this was a model of directional transponder used by scouts and military personnel. Like its smaller cousin, the survey datapad, this briefcase-sized device contains topographical information on a variety of planets. This data is easily updatable from commercial sources. The Graph 18 provides up-to-the-minute charting of the unit's location on a given planet, allowing field personnel to track their progress without getting too lost. The Graph 18 can store information on up to 25,000 different planets.