Portable AC/DC printing calculator features a large 12-digit liquid crystal display (LCD), and two-color serial printer with punctuation. Prints at approximately 2 lines per second with positive numbers in black, negative numbers in red) on standard-size paper rolls. Features clock and calendar function, and prints date and time. Cost/sell/margin keys allow convenient calculation of cost price, selling price and margins. Tax keys allow for easy tax calculations. Change calculation mode works as cash register. Enter total amount, type in currency received and change will be calculated. Four-key memory includes memory plus, memory minus, recall memory and clear memory. Additional features include mark-up and +/- key, floating (F) or fixed decimal (3,2,0), add (A) mode, and heavy-duty metal paper holder. Includes AC adapter. Uses four AA batteries (sold separately).