The SR-40 is a scientific calculator with the usual bunch of
scientific functions and also memory.
It is almost identical to the TI-30 which was introduced simultaneously with this one. The main difference is that the SR-40 came with a battery pack, but the TI-30 used a 9V battery. And the SR-40 looks a little bit more professional.
It is functionally identical to the TI 45 which has a fluorescent display.
©2023 Ernst Mulder