The Casio® MS-80B eight-digit desktop calculator meets a variety of business needs. Keep this calculator at your desk for whenever you need answers to math problems. Streamline financial calculations with tax calculation, currency conversion and profit margin functions. Can be operated from solar or battery power, so you can use the calculator both day and night. Three-key memory keeps often used figures accessible for faster calculations, Square root, rounding switch, sign change, grand total, and percent functions help you solve a variety of mathematical problems. Key rollover feature makes sure nothing is lost during high-speed input. Keys are made of plastic.