This four-function calculator has a tan plastic case, an array of ten oval digit keys, and a decimal point key. It also has four blue arithmetic function keys to the right of these and has clear entry and clear keys to the left. A constant switch is above the clear keys. The on/off switch is on the right above the keyboard. A mark to the left of it reads: JCPenney. The eight-digit LED display is at the back. The back edge has a socket for a power adapter.
A sticker on the back reads: JCPenney (/) Electronic Calculator (/) VOLTAGE 6V CURRENT 0.2A (/) MODEL MM3R SERIAL No. 126131 (/) Made in U.S. A.
This model is similar to the Commodore MM3R and probably was made by Commodore.
J. C. Penney is a chain of American department stores.
Guy Ball and Bruce Flamm, The Complete Collector’s Guide to Pocket Calculators, Tustin, CA: Wilson/Barnett, 1997, pp. 81–82.
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