Utility droids of all makes and models have been a common sight throughout the galaxy for millennia. The versatility of these handy little droids, combined with their reliable programming and affordability, has made them popular for everything from light janitorial duties to complex mechanical repairs and maintenance.
Among the premier utility droids available four thousand years ago were those in the T3 series. Though more expensive than most standard models, T3 droids contained the latest in advanced circuitry and programming, and were easily fitted with a variety of customized upgrades.
Crafted on Taris, T3-M4 was an early prototype of a late-generation model in this prestigious line. Janice Nall, a droid proprietor on Taris, customized the droid to serve as a personal security unit for an anonymous buyer -- Davik Kang, the local crime lord for the Exchange.
Along with the standard functionality, T3-M4 was equipped with light armor plating and upgradeable weapon functionality. Its programming was adjusted so that the droid could readily attack sentients. It had formidable fighting abilities coupled with its innate computer slicing and code breaking skills, all contained within an appealing, innocuous shell. T3-M4 spoke in a trilling, information-dense droid language.
Canderous Ordo, a Mandalorian mercenary operating on Taris, was to take delivery of the droid for Kang, but secretly cheated the crime lord. Instead, he sent others on an errand to purchase the droid on his behalf, and used T3-M4 to slice into the Taris computer network, obtaining access codes allowing Canderous to leave the blockaded planet.
T3-M4 accompanied Ordo along with Carth Onasi, Bastila Shan and other Republic luminaries during the Star Forge crisis, four thousand years before the Battle of Yavin.
T3-M4 is the KOTOR equivalent to R2-D2, but packs much more weaponry than the classic astromech ever did. In the game, T3-M4's major contributions are as a slicer, being able to bypass locked doors and hack into computer systems. It can also manufacture a finite number of computer spikes -- tools necessary for other characters to slice into computer networks.