"Size: about 15 cm/5.9 inches long and 12 cm/4.7 inches wide. "Features: The calculator has two power sources, solar (works only when bright) and battery (battery not included), large 12-digit display with large ABS plastic buttons designed to add, subtract, multiply, divide, backspace, % and MU. automatically turns off when not in use for approximately 10 minutes.Ideal for people: It is perfect for the home and office, performs common math operations and various financial functions, and is ideal for adults and students."Note: Some users may use desktop computing early in the morning or at night. Without battery power, it may be difficult to see the screen in low light conditions, and it is recommended that you insert AA batteries for continuous and accurate use. "After Sales: Make sure we provide good service, if for any reason you are not satisfied with your product purchase, you will receive a full refund or money back guarantee. Upgraded versionCalculator, 12-Digit Solar Cell Office Calculator with Large LCD Display, Large Sensitive Buttons, Dual Power Desktop CalculatorSuitable for Office, Home, School