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Imperial 91S

The Imperial 91S is an arithmetic calculator with 8 digits precision and algebraic logic. It has 9 functions, 27 keys, and a VFD (vacuum fluorescent) display. The power source is 4xAAA.

Facts at a glance:

FeatureValue
TypeArithmetic
Functions9
Keys27
Precision8
LogicAlgebraic
Display typeVFD
Length120mm
Width73mm
Thickness20mm
Weight116g
Power Source4xAAA
Year introduced1976
Year discontinued1976

Replacements:

If you have an Imperial 91S that is no longer working, you can first try replacing the 4xAAA batteries. If that doesn't solve the problem, then you can consider replacing the calculator with a modern equivalent. We suggest the following current models as possible replacements:

See other calculators by Imperial