In July 2001 Lexmark introduced the T520, T522 two of the four new base models of their T-series laser printers. After seven years of Optra products, the name was dropped, simplifying the model numbering scheme. Many of the features of the original Optra T-series were retained, with these latest T-machines containing new, faster engines based on Lexmark engine technology. The physical design was unchanged from that of their predecessors, but the engines were redesigned for faster performance and paper handling, and the print cartridges were modified to make them incompatible with the Optra models.

T520 and T522 models are mostly identical, except for speed and duty cycles. They replace the Optra M410 and M412 printers, and their cartridges include a smart chip similar to, but more powerful than those in the Optra T-series, with a "signature" feature added. Print speeds were increased, as were duty cycles and toner yields.

The new series includes the base T520 and T522, the network-ready T520n and T522n, a T520d with duplex unit standard, and T520dn and T522dn network-ready models with duplex units standard. All seven models use the same print cartridges.

The T520 and T522 printers were targeted at small-to-medium size workgroups, and both shipped with 5,000-page starter cartridges. Standard and high yield cartridges in both Prebate and non-Prebate versions are available, as well as a MICR cartridge and a high yield Prebate cartridge for special label applications.

Source Technologies ST9120 MICR