Abstract: An operator changeable and disposable ribbon cassette of molded plastic serves as a protective guard and as a part of the cabinetry on a printer and has a built-in tear-off edge for paper. The ribbon, ribbon guides and ribbon drive rollers are angled at two degrees with respect to the line of print wires or line of printing to make better use of the ribbon width, and the cassette includes a ribbon tension spring and a drive pressure spring, the tension spring being used to maintain the endless ribbon in a desired position upon exit from a stuffing box portion of the cassette and the drive pressure spring being a part of the drive roller mechanism for driving the ribbon in a continuous manner. The cassette is connected to the printer framework and includes cam surfaces and latches to hold the cassette in place on the printer.