A compact scanning eyepiece that lets its wearer look through solid walls at close range, paired with a modified TR-116 rifle by the killer in Field of Fire.
The exographic targeting sensor is a small headset fitted over one eye. It gives the user a magnified view through solid matter across a considerable distance. It appears in the Deep Space Nine episode Field of Fire.
A murderer aboard the station combines the sensor with a TR-116 projectile rifle fitted with a micro-transporter. Sighting through decks and bulkheads, the killer beams each bullet to a point just in front of a victim in another room.
O'Brien works out the method and builds a copy. Ezri Dax, guided by the memories of the murderous former host Joran, uses the sensor to scan crew quarters and identifies the Vulcan officer Chu'lak, then shoots him through the walls as he aims at her.