The CMB1001BK with Calculator is an electronic part manufactured by Citizen. It is a basic, 2-in-1, ten-digit desktop calculator with a digital display and clock. The calculator is dual powered by battery and AC adaptor. It features a 2 line LCD display, which includes 8-digit main display and 10-digit memory display. The calculator includes basic math functions, such as addition, subtraction, multiplication, and division. It also has a 24-hour clock mode with alarm clock, stopwatch, and countdown timer functions. The calculator is perfect for basic calculations, timekeeping, and more. It is a lightweight and portable device that can easily fit in a desk drawer or briefcase.