This vintage RARE CASIO fx-8100B Scientific Calculator Chronograph is in good condition and includes the original black vinyl case (see photos). Although it says “fx-8100” on the front the model number given on the back is “fx-8100B” on the back (see photos). It uses two SR 1130 (G-10) 1.5 V button-cell batteries. The batteries were removed as a precaution long ago and the battery compartment is clean and completely free of corrosion (see photos). The front of the black vinyl case has some wear (see photos).
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