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Up for sale is a stunning and rare example of mid-century engineering: the Royal Resulta 7 mechanical calculator. Manufactured in West Germany by Maschinen- und Werkzeugfabrik Paul Brüning, this "toothed-wheel" adding machine is as much a work of industrial art as it is a functional tool.
Key Rarities & Collector Features:
Rare Red "Wrinkle" Finish: While many Resulta machines were finished in a standard industrial green or grey, this unit features the highly sought-after vibrant red crackle/wrinkle paint. This finish is famously durable and remains in very good condition.
Royal Branding: This unit carries the prestigious "Royal" badge, indicating it was imported and distributed by the American Royal Typewriter Company. These cross-branded models are significantly harder to find than the standard Resulta-only versions.
Early "Patents Applied For" Status: The front plate indicates it was produced during a specific early window of production before international patents were finalized, adding a layer of historical interest for collectors.
7-Digit Capacity: The "7" model provides a robust 7-digit upper register and input display, capable of handling totals up to 9,999,999.
Condition:
Functional: The machine has been tested for addition and subtraction. The internal gears move smoothly, and the results clear correctly via the side handle.
Aesthetic: The red finish is bright and clean with minimal wear. The original manufacturer's instruction label on the underside is fully intact and legible—a rare find for a machine of this age!
Originality: This machine is 100% original. No modern parts or repainting.
