Commercial dual power desktop calculator offers a 12-digit liquid crystal display (LCD) with automatic 3-digit punctuation. Multiple Use key simplifies business calculations to save time and increases efficiency by handling functions like margin, markup, selling prices, costs, percent changes. Functions include independently accessible four-key memory plus second two-key memory function, round up/off/down, add mode, fixed (3, 2, 0)/ floating decimal, and Constant and Sigma mode selectors. Solar-powered operation with battery backup prevents memory loss. Twin power sources include built-in solar cell and lithium cell. Calculator includes adjustable stand and carrying case and weighs .64 lb.