12 Digit Ergonomic Large Desktop Calculator Solar/battery powered Aluminium front plate and extra large anti-slip rubber feet Silent touch plus durable anti-fade plastic keys, markings do not wear, as being injected into the key Numeric keypad configured with 0 key below 1 key Advanced Percentage Calculation, Currency Conversion with 3 storable rates, Mark-Up Calculation via % key Square Root Calculation, Rounding Options, 0-5 decimal digits selectable Constant Calculation, GT Grand Total Sum Memory, Summarising 4-key Memory, Backspace key 00 double zero key, +/- key for algebraic sign change 3-Key Rollover - Input Buffer Memory, enables very fast input typing