Genuine OEM Lexmark Optra T610 Toners
The Optra T610's smaller black-toner option is the 12A5840 cartridge. High-yield 12A5845 toner gives you more printing between changes. Both belong to Lexmark's Return Program, which requires sending the empty cartridge back to Lexmark.
Toner Buzz carries genuine Lexmark toner for the T610, including those Return Program options and high-yield 12A5745 toner without the program's return terms. For label printing, 12A5849 is the purpose-specific toner choice. The separate 99A1017 charge roller is a maintenance part, not a toner cartridge.