Large, 12 Digit Professional Large Desktop Calculator, Kick Stand Display Is Perfect For Business Professionals Home OrOffice, Modern White Design, Features A Large LCD Display & Large Durable Plastic Keys, Cost/Sell/Margin Keys Make For Quick & Easy Profit Margin Calculations Simply Enter 2 Variables & The Third Automatically Appears, Includes Grand TotalKey, Double Zero Key, Backspace Key, Automatic Tax Keys, Percent Key, 4 Key Independent Memory, Extra Large Plus Key, Sign Change & Automatic Power Down, Operates On Twin Power Solar/Battery Backup.