Large Key Calculators Office Desktop Calculator, Dual Power Electronic Comfortable Computer Key Buttons: The Special computer key button is higher than the common computer and it increases the resiliency of this button. It cannot be stuck easily during you use it. The big figure button can help the aged seeing clearly and using it happily. Enhanced LCD Display Screen: We use the specially modulated pigment for the display screen which improves the clarity of the display screen greatly. Dual Power Energy Saving: The powers are battery and solar (one AA battery NOT included). The Solar design make the calculator can work in daytime or even in the dim light without battery. Special Functions: When you would like to calculate the number, it will express the symbol (plus, subtract, multiply or divide) on the screen. It can help you seeing the operation step when you operate continuously Apply For: It perfects for office, business, school, store, mall and home use. It supports touch typing by user such as bank stuff, financial worker, front Desk clerk and data analyst etc.