Medium, 10 Digit Professional Desktop Calculator, Perfect For Business Professionals At Home Or In The Office, Modern White Design, Features A Large Angled LCD Display & Durable Plastic Keys, Cost/Sell/Margin Keys Make For Quick & Easy Profit Margin Calculations Simply Enter 2 Variables & The Third Automatically Appears, Includes Currency Conversion Functions, Automatic Tax Keys, Percent Key, Backspace Key, 4 Key Independent Memory, Extra Large Plus Key, Sign Change, & Automatic Power Down, Operates On Twin Power Solar/Battery Backup.