These products are guaranteed to work with your Lexmark T640n printer.
Lexmark T640n is a Workgroup monochrome laser printer which prints at a speed of 35 pages per minute with a maximum resolution up to 1200 x 1200 dpi. This printer is installed with a typical memory of 64MB which can be expandable to 576MB and the processor used in this printer is 400 MHz. The printer is having a user friendly control panel with four line APA backlit grey scale display. The printer is network ready with Parallel port, Ethernet (RJ-45), one internal card slot, one USB on the front and one USB at rear.