Product Description: The Monroe Difference As the inventor of the commercial printing calculator in 1912, Monroe has earned the trust of Fortune 500 companies, non-profit organizations, and government agencies, including the likes of NASA. Even Hollywood has recognized the strength of the Monroe brand as its products have landed on major television networks and hit series including the show Madmen. Monroe Systems for Business are forerunners in producing technology tools that empower businesses, schools, and individuals to succeed. Headquartered in Pennsylvania, Monroe has a continued commitment to creating durable and reliable products, along with providing superior customer support known as 'The Monroe Spirit'. Don't deal with the mess of getting ribbon ink on your hands, use Monroe's P71M, a high-quality, easy-to-install ribbon cartridge instead of ribbon spools. Having the highest standards in the calculator industry, Monroe produces the darkest printing black/red ribbon cartridges on the market. Monroe pushed every envelope when designing a ribbon with the highest possible inking degree, and eliminated the risk of ink smudges. Monroe requires their factory to use a true red ink that is extremely rich in color and used specifically by Monroe, unlike the orange tint you see in watered-down versions from other brands. Monroe's engineers developed the most convenient calculator ribbon to install. They created the first-ever cartridge containing a calculator ribbon, which provides you with the easiest installation. To maintain the darkest print on their paper tape, users of Monroe products are suggested to change their ribbons after replacing 3 paper tape rolls. Designed for Monroe calculators and compatible with other brands and models.