Sentry droid

Sentry droids or patrol droids were droids that acted as sentries in various locations.Star Wars Rebels: Recon Missions They were often similar in design and function to probe droids. 
During the Galactic Empire's occupation of Lothal, a model of sentry droid was deployed to patrol Imperial installations. The droid used on Lothal often operated in groups of three, and was visually similar to the observation droid used by the Galactic Republic during the Clone Wars, for they both sported a large, central red photoreceptor as well as an antenna. However, the Imperial Lothal model had an additional built-in blaster with a barrel portruding from the droid's body, from which it was able to rotate around. IMG-099 Imperial Mark IV patrol droids were employed by the Galactic Empire to scout and surveil areas on planets such as the streets of Mos Eisley Tatooine. 
The Empire also employed DT-series sentry droids and these models were also used as were used as guardsStar Wars Jedi: Survivor and combat training droids.
The patrol droids of the First Order were deployed in and around the installations of Starkiller Base,Star Wars: The Force Awakens novelization and were equipped with a long-range communications antenna.Star Wars: The Force Awakens: The Visual Dictionary
==Appearances==
==Sources==
*Star Wars: The Force Awakens: The Visual Dictionary 
*Star Wars: Complete Locations
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*Cyphers and Masks
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*Ultimate Star Wars, New Edition
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==Notes and references==
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