DESC: Features: Twin-Powered Basic Hand-Held Calculator with Extra-Large Display and Attached Hard Cover. Extra-large Display, 8-digit (13.5 mm) LCD display with punctuation. Twin Power Solar Operation, automatically switches from solar to battery power in low light. 3-Key Memory, includes memory plus, memory minus and recall/clear memory keys. Additional Features: percent square root keys and sign change keys, automatic power off, slant display, and hard cover attached.