Big Buttons, A 5-Inch Lcd Display, Dual Power, Solar Power, And A Built-In Pen Built in Pen and Pencil Holder: The extra large calculator is designed with two cavities at the top holding two pens or two pencils or one of each. Big buttons Computer keyboard type big keys easy to press with fingers. Extra Large LCD Display - This Desk Calculator features an extra large 5 inch LCD display, making it easy to read and convenient for all your tax calculation needs. 12 Digit Capacity - With a 12 digit capacity, this calculator is perfect for large calculations, making it ideal for office use, school work, or financial calculations. Easy to Use and Portable - This calculator is designed with big buttons and a large display making it user-friendly and perfect for both adults and kids., The Jumbo sized calcuilator is designed to sit flat on a desk, countertop, or table for convenient access, this calculator is easy to carry making it perfect for use at home, in the office, or on the go. Two Way Power - The calculator operates on both solar and battery power, ensuring reliable use in any lighting condition. Requires 1 "AA" battery (not included)