Abstract: The twintractor is a device designed to be incorporated into a wide carriage personal computer printer, or supplied as an accessory to such a printer or a typewriter, giving it the capability of transporting and printing upon, in the alternative, one of two continuous paper media. The availability of such a device will provide the users of personal computers or typewriters with the flexiblility to print jobs on more than one kind of paper output media without the repeated necessity of changing paper encountered in standard 80-column width printers or carriages. A means for changing the zero position or left margin for the print head when the choice of print media is made is also incorporated in the device, as well as paper sensors, paper parking detectors, and removable tractors.