u/DGram2020

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​Brand: Seiko.

​Model: 88-5011 (ACRP series).

​Movement: Manual wind mechanical movement, Cal. 8800B (7 Jewels).

​The Dial: High-speed 30-second main rotation (one full revolution = 30 seconds) allowing for precise 1/10th of a second readings.

​Registers: 15-minute sub-dial recorder.

​Case: approx. 50 mm diameter.

​Crystal: Original Plexiglass.

​Origin: Made in Japan.

​Condition Details:

​Functionality: The stopwatch is working properly and snaps back to zero perfectly.

​Dial: Excellent vintage condition, very clean with high-contrast black and red scale markers.

​Case: Good vintage condition with visible signs of age and an honest patina, showing its history as a professional timing tool.

​Internal: The movement is very clean and well-preserved.

Timestamp & Album:

https://photos.google.com/share/AF1QipPhUM-vzZ1YH5jRqtFZhxxV0yq8seCMdsN42dX\_vjjXTmYzd6DVPeTuw37-lAskLg?key=bURoakRMTlFMTFNJRFN2VTEyQjItVWN3RVV5aHNn

Shipping & Payment

Price: $87 Free Shipping

Set: StopWatch only.

Shipping: Worldwide from Ukraine, fully tracked (~2-2,5 weeks delivery)

Customs: Can be discussed with the buyer.

Payment: PayPal (F&F), USDT / Crypto (negotiable).

Please comment before sending a PM/Chat.

Feel free to reach out with any questions!

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HISTORICAL AND HOROLOGICAL CONTEXT

​This exceptional timepiece represents a critical post-war milestone in the history of Japanese watchmaking. Following the devastation of World War II, the Kameido factory was initially non-operational, leading Seikosha to restart production via its Suwa facility in 1946 with the New 10A movement.

By 1948, the Kameido factory resumed operations, producing the celebrated Kameido New 10B, also known colloquially as the Kameido Shinto. This watch is a definitive final-phase iteration of that recovery era, manufactured in February 1955.

​While 7-jewel variants of this caliber account for roughly 60% of total production, top-grade 15-jewel executions like this one are incredibly rare, representing only about 10% of the total output. Crucially, this specific movement features the highly desirable 3 ADJ (Three Adjustments) factory tuning, making it a premium high-precision chronometer-grade execution for its day.

It showcases high-end vintage movement finishing, including a nickel-rhodium plated bridge plate, a square-hole wheel, a round-hole wheel with a one-way decorative groove, and gold engraving on the receiver plate. This timepiece stands as a true foundation stone from which the global legacy of modern SEIKO was built, making it an incredibly scarce find for serious collectors of historical horology, especially in its pristine dead stock condition.

​DETAILED TECHNICAL SPECIFICATIONS

​Brand and Model: SEIKO Kameido New 10B (Shinto / Post-War First Milestone Late Model)

​Movement / Caliber: Seikosha New 10B, Top-Grade Factory 3 Adjustments (3 ADJ.)

​Movement Type: Mechanical manual-wind, sub-second, without seconds hacking mechanism

​Jewels: 15 Jewels (Highly rare top-tier adjusted execution)

​Frequency: 18,000 vph (5 beats per second / Vintage Low-beat)

​Power Reserve: Approximately 36-38 hours (when fully wound)

​Case Material: Stainless Steel (SS Back / Snap-back case with the iconic early-period crane engraving, reference number 13030)

​Case Dimensions: Length approx. 37mm including lugs / Width approx. 31mm excluding crown / Thickness approx. 10mm

​Lug Width: Approx. 16mm

​Weight: 28g

​Crystal: High-grade Acrylic / Plexiglass

​Dial and Hands: Two-step two-tone circle sector dial with a gold floating S logo, large wedge hour markers, flying Arabic numerals at 12, 3, 6, and 9 o'clock. Gold-tone leaf/alpha hands and a circular-grained sub-second register at 6 o'clock.

​Band/Strap and Buckle: Paired with an authentic, period-correct late 1940s dead stock brown leather stitched strap (showing minor signs of age from storage) with a classic steel pin buckle.

​CONDITION REPORT

​Cosmetic Condition: This watch is preserved in astonishing New Old Stock / Dead Stock condition. The stainless steel case and snap-back crane-engraved case back are incredibly crisp with sharp factory lines, displaying only minor, negligible storage and handling marks over its 70-year lifespan. The acrylic crystal remains beautifully clear. The original two-tone sector dial and gold hands are exceptionally clean, showcasing a stunning, uniform light vintage ivory patina that confirms its 100% original, untouched state.

​Mechanical Condition: The movement functions beautifully. Time setting operates smoothly and the sub-seconds hand runs continuously with excellent amplitude. It is currently maintaining an excellent daily rate accuracy of approximately plus/minus 30 seconds per day, which is outstanding for an unshock-protected movement from this era.

​Service History: Fully overhauled and serviced recently. The inner case back bears a professional horological service signature dated October 17, 2023 (2023.10.17). Please note that because this mechanical movement is approximately 70 years old, it contains no modern shock protection and must be handled with appropriate care.

​BOX AND PAPERS

​Accessories: Full vintage presentation set. Includes a genuine, rare late-model SEIKO manufacturer's high-end storage case featuring gold embroidery inside velvet lining, alongside its original outer paper protective box (both showing light, authentic signs of age).

No papers.

Album & Timestamp:

https://photos.google.com/share/AF1QipMBRk8LIVFlWhjGDegY7uj5u9\_FR3uIsfnD2MxZLnisu1zpNhA5v6PPjUqUcTb4xQ?key=NzBNS3Jkbk0yS1ptMllOcDVhVWJCQ2pQUmxvV3V3

Price:$ 540

Payment: PayPal, Zelle (Other options are also possible, but by agreement).

​Location: USA

Worldwide Shipping

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