12-digit calculator provides extra heavy-duty durability that's perfect for power users and the everyday advanced user in busy office settings. Large, fluorescent display offers easy viewing to help prevent reading errors. Two-color, 4.5 line-per-second ribbon printer is fast and reliable for consistently legible results. Professional keyboard layout with a left-side total key helps you quickly and accurately input data for fast calculations with minimal errors. AC-powered calculator also includes four independent memory, change sign key, average key, backspace key, double-zero key, tax calculations, calendar/clock function and more.