Casio Computer Co. Casio fx-85 Scientific High Power Solar Cell Calculator | eBay
Casio Fx-82ms 2nd Edition 240 Functions Scientfic Grey Calculator for sale online | eBay
Casio - FX-82MS. I bought it in high school, used it in University and now on my 4th year as a Professional Accountant. Haven't changed the battery once. : r/BuyItForLife