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Rockwell 21R (MEMORY)

Rockwell 21R
Image: Joe Haupt, CC BY-SA 2.0

The Rockwell 21R is an arithmetic calculator with 8 digits precision and algebraic logic. It has 5 functions, 20 keys, and an LED (light-emitting diode) display typical of calculators of this era. The power source is PP3 9V.

Facts at a glance:

FeatureValue
TypeArithmetic
Functions5
Keys20
Precision8
LogicAlgebraic
Display typeLED
Length155mm
Width76mm
Weight140g
Power SourcePP3 9V
Year introduced1975
Year discontinued1975

Replacements:

If you have a Rockwell 21R that is no longer working, you can first try replacing the PP3 9V battery. 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 Rockwell