GT astromech droids, also referred to as GT models, represented a specific class of astromech droid deployed by Pathfinder teams. One example is GT-11, an astromech of the GT variety who served within the pathfinder team led by Jedi Master Silandra Sho. Another GT astromech droid, GT-22, was part of the Galactic Republic's Outer Rim Exploration Team during Outer Rim Expedition Eight-Zero-Seven. Circa 379 BBY, a salmaca that had been attacking the village of Peka for a number of weeks stole the droid Dee-Twelve. Jerlyn, whose family possessed Dee-Twelve, gave a description of it to Jedi Padawan Rooper Nitani, who had offered to assist in the droid's recovery, and he noted its size and form were reminiscent of a GT model.
The existence of GT astromechs was initially revealed in the 2023 reference publication, Star Wars: The High Republic Character Encyclopedia. Their designation as GT models originated in the short story "Shield of the Jedi," penned by George Mann and featured in the 2023 young-adult collection, The High Republic: Tales of Light and Life.