citizen 4 520670 challenge diver
Citizen
4-520670

Challenge Diver

Automatic, Japan 1971. Correct bezel insert, crisp case, JDM market only.

$960
Available

One of Citizen’s first serious dive watches, built for the domestic market at the start of the 1970s. The Challenge Diver combines a purposeful cushion case with bold lume and a rotating bezel - a rare find in crisp condition.

At a glance

Reference
4-520670
Year
1971
Movement / Caliber
Citizen automatic, 21 jewels
Case Size
41 mm (width)
Lug Width
20 mm
Functions
Date · Rotating bezel
Market
Japan (JDM)
Serial / Date
1xxxxxxx · 1971
Case Reference
4-520670 (caseback)
Crystal
Mineral
Bracelet
Aftermarket rubber strap
Bracelet Sizing
Fits approx. 16–21 cm wrist
Water Resistance
150 m (rated, not tested)
Other
Correct bezel insert · Screw-down caseback
Dial
Appears original. Even aging to luminous markers.
Hands
Believed original. Lume matches dial markers.
Case
Crisp case with light wear consistent with age.
Crystal
Mineral. Originality not independently verified. Minor surface scratches.
Bezel
Correct insert. Light fading and small marks.
Crown
Appears original Citizen, operates smoothly.
Bracelet / Strap
Aftermarket rubber strap, not original to the watch.
Replacement / Restored Components
Strap replaced. No other known replacement or restored components.
Overall Condition
Very good vintage condition.

HOW WE ASSESS

Condition, originality, function and service history are assessed from our inspection and the information available to us. Where something cannot be independently verified, we say so.

Latest finds

Not every watch is worth collecting. We seek out the ones that are.

The Citizen Challenge Diver was one of Citizen’s first serious dive watches, built at the start of the 1970s for the domestic Japanese market. Its cushion case, bold luminous markers and rotating bezel give it a purposeful tool-watch character that still feels distinctive today.

Powered by an in-house Citizen automatic movement, it was designed for reliability and everyday wear rather than refinement for its own sake – which is exactly why so many examples were worn hard and so few survive in crisp condition.

With a correct bezel insert and well-preserved case, this example is a strong representative of early Citizen dive watches and a less common alternative to the more familiar Seiko divers of the era.

Group 57 (1)

Found there. Collected here.

Japan's watchmaking history extends far beyond the familiar names and celebrated references. We search across Japan for watches with character, history and a reason to be collected—from recognized classics to remarkable pieces that have been overlooked along the way.

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