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:
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: