![Stephen Fahey on Twitter: "Just realised my Casio calculator is nearly 30 years old. Still works perfectly http://t.co/qIqFLOoDpL" / Twitter Stephen Fahey on Twitter: "Just realised my Casio calculator is nearly 30 years old. Still works perfectly http://t.co/qIqFLOoDpL" / Twitter](https://pbs.twimg.com/media/CGuHOWzXEAAazVF.jpg)
Stephen Fahey on Twitter: "Just realised my Casio calculator is nearly 30 years old. Still works perfectly http://t.co/qIqFLOoDpL" / Twitter
![Amazon.com : Casio FX300ESPLUS FX-300ESPLUS Scientific Calculator, 10-Digit, Natural Textbook Display, LCD : Office Products Amazon.com : Casio FX300ESPLUS FX-300ESPLUS Scientific Calculator, 10-Digit, Natural Textbook Display, LCD : Office Products](https://m.media-amazon.com/images/I/41gPSjofXOL._AC_.jpg)
Amazon.com : Casio FX300ESPLUS FX-300ESPLUS Scientific Calculator, 10-Digit, Natural Textbook Display, LCD : Office Products
![Vintage Casio fx-450 Solar Cell Scientific Calculator Working Condition for Sale in Pelham, NH - OfferUp Vintage Casio fx-450 Solar Cell Scientific Calculator Working Condition for Sale in Pelham, NH - OfferUp](https://images.offerup.com/WOz3GGRE7h47CYPDdJKzTuoUlwQ=/1170x1439/4d61/4d61e67ef097492d871b8cb2895e4429.jpg)