Casio fx 31. Dad bought this during his college days in 1978. Running flawlessly since 41 years now. I use it sometimes when I'm bored of using my phone. : r/BuyItForLife
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VINTAGE CASIO FX-31 VFD Scientific Calculator Good Condition WORKING £20.00 - PicClick UK
Casio fx 31. Dad bought this during his college days in 1978. Running flawlessly since 41 years now. I use it sometimes when I'm bored of using my phone. : r/BuyItForLife