Performs 417 scientific and math functions, making it ideal for students, professionals, and engineers. The 15-digit display and four display lines allow for longer, more complex formulas. Dual solar/battery power provides reliable functionality in all lighting conditions. Auto shutoff feature helps conserve battery power. Convenient hard shell sliding cover protects the calculator from scratches. Power Source(s): Battery; Solar; Display Notation: Numeric; Number of Display Digits: 15; Display Characters x Display Lines: 15 x 4.