Brand: CASIO
Model: fx-82D
Type: Scientific calculator
Picture: CASIO fx-82D
Batteries: AA x 1
Lifetime: Introduced: around 1989?
Terminated: unknown
Notes: The CASIO fx-82 series started with the CASIO fx-82, an ordinary scientific calculator. But But CASIO kept extending this line, turning it not into just a model number but a whole calculator series. Trying to make it the non-programmable scientific calculator for school use.

So far I've found mention of the following types:

Enhanced version of the CASIO fx-82C. The added feature is the fraction key.