The original T1 series of droids—the T1-series bulk-loading droid—were manufactured by Kellenech Technologies before the Great Sith War, but the company collapsed in the following years. Its assets were liquidated and the T1-series trademark was purchased by Duwani Mechanical Products.
The new owners of the trademark manufactured their unrelated T1-series of utility droids using the designation, and as a result, Kellenech's old T1-series became commonly known as the "LB"-series so as to differentiate it from the newer production model.