Monroe P71M Black/Red Ribbon Cartridges 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. Years back, the P71M was referred to as the Marc 2 or Marc II ribbon. 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. Those who know, choose Monroe.