A business printing calculator without the paper. Twelve-digit desktop calculator that allows you to check up to 150 steps and make corrections. Double zero and triple zero (00, 000) keys let you imput large numbers. Backspace key erases mistakenly entered digits and helps you from having to start over. Other functions include review and auto review, go-to function, correct key, GT memory and three-key memory. Power Source(s): Battery; Solar; Display Notation: Numeric; Number of Display Digits: 12; Display Characters x Display Lines: 1.