The Royal 4HPD is an arithmetic calculator with 10 digits precision and algebraic logic. It has 10 functions, 30 keys, and an LCD (liquid crystal) display. The power source is 4xAA.
Facts at a glance:
If you have a Royal 4HPD that is no longer working, you can first try replacing the 4xAA 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: