The Casio FX-991ES Plus Emulator is a piece of software that mimics the hardware and software of the physical Casio fx-991ES PLUS scientific calculator on a Windows computer. It is a standalone digital product, part of the fx-ES PLUS series of emulators from Casio, which supports a wide range of models including the fx-82ES PLUS, fx-85ES PLUS, fx-350ES PLUS, and the target fx-991ES PLUS.
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