The TX-series Astromech Droid was the first dedicated astromech droid to hit the Confederate market. Introduced in 98 BBY, it became an instant hit. Even when trade with the known galaxy gave access to the R-series of astromechs, most Confederate citizens preferred the proven TX-series. Even the Y-wings, called Manta Rays, and later the ARC-170s (a variant called the Venom, in Confederate service, were modified to accept TX-series droids instead of the usual R-series droids.
By 18 ABY, the TX-series had reached its third incarnation, the famous TX-3. The TX-3 was still going strong by 41 ABY, though by then Republic DroidWorks were working hard on its successor, the TX-4.