Brand: SUNDEER Energy saving: Automatically turn off the power to save more energy. Attention: Please insert an AA battery for continuous and accurate use. 12 digit calculator: 12 digits make calculators very useful in large calculations. Suitable for businessmen, workers, teachers, students, or anyone who needs to calculate from time to time. Large button design: Large non stick plastic button, made of new materials, more durable. This calculator features a scientifically designed large button that conforms to human habits and provides a comfortable touch. Large display screen: large eye angle, upright display, easy to read, convenient to carry.