Victor TUFFCALC Desktop Calculator, 12-Digit LCDWater- and shock-resistant calculator is ideal for on-the-go professionals. Sealed rubber keypad and acrylic coated display may be cleaned with soap and water. Soft, contoured keys enable silent data entry. Convenient tax keys are easy to set. Large LCD is easy on the eyes. Power Source(s): Solar; Display Notation: Numeric; Number of Display Digits: 12; Display Characters x Display Lines: 12 x 1.