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Seiko Prospex First Japanese Diver’s Re-interpretation Automatic Black Dial Nylon Strap Mens Watch SPB239J1

Product Code: SPB239J1 Categories: , , ,


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Seiko Prospex First Japanese Diver’s Re-interpretation Automatic Black Dial Nylon Strap Mens Watch SPB239J1

Seiko Prospex Mens SPB239J1 First Japanese Diver’s Black Watch.  This 2021 design is inspired by Japan’s first diving watch, created by Seiko back in 1965. This 2021 version comes with calibre 6R35 and its long-lasting 70 hour power reserve, accompanied by Seiko’s first ever original nylon strap for diver’s watches – the ‘SEICHU,” crafted in Japan, designed for flexibility and durability.


Prospex is a combination of the words ‘Professional’ and ‘Specifications.’ Seiko Prospex timepieces are designed to be practical, reliable and durable; to meet the high standards required in extreme environments for sports lovers and adventure seekers alike.  Since launching Japan’s first diver’s watch in 1965, Seiko’s innovative watchmaking has changed global dive watch standards.

The Case:

The Seiko Prospex Mens SPB239J1 First Japanese Diver’s Re-interpretation has a stainless steel case measuring 40.5mm in diameter, with a thickness of 13.2mm. With the signature oversized crown, this watch manages to meld the rugged with the timelessly cool. The use of a black unidirectional bezel brings further depth and character, with another retro touch coming from the curved lugs.


The use of sapphire glass makes this a truly sturdy timepiece, reflecting the fact that the The Seiko Prospex First Japanese Diver’s Re-interpretation was built with the modern user in mind.

The Dial:

The new iteration of the Seiko Prospex comes with a dial in a deep shade of black. Somewhat more subdued than other versions, this Seiko Prospex model is ideal for those seeking a watch packed with the kind of classic athleticism that made this series such a hit. The dial has a date aperture at three o’clock in addition to super-legible indices and markers. Lumibrite features on the hands and indexes for top legibility in all scenarios, making this a functional dial.

The Strap:

The bracelet of the Seiko Prospex First Japanese Diver’s Re-interpretation comes in a unique nylon that is far from the average material. Seiko’s first ever original nylon strap for diver’s watches – the ‘SEICHU,” this was crafted in Japan and designed specifically to ensure longevity, versatility and strength. Add to this the undeniable vintage charm of this bracelet and it is yet another element on this watch that marries perfectly with the rest.


The Function:

Though inspired by tradition, this Seiko Prospex remains a profoundly modern technological watch. With a powerful Caliber 6R35 boasting 24 jewels, this Prospex is as elegant a timekeeper as they come. Add a seventy hour power reserve and the fact that this watch is water-resistant to 200m and it’s clear that Seiko have outdone themselves once more.


Also, the The Seiko Prospex First Japanese Diver’s Re-interpretation has a date function making it the perfect daily watch for any watch lover.


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Additional information





Face Colour








Strap Colour





2 year manufacturer's warranty





Case Size


Strap Type


Water Resistency



Automatic (Self-Wind and Manual Wind)


Sapphire Crystal

Clasp Type

Pin Buckle

Watch Style

Diver (200m+)

Case Material

Stainless Steel

Case Finish


Caseback Style


Caseback Fastening


Crown Type

Screw-Down Crown

Crown Finish


Dial Style


Display Type


Day Display

Day / Date – English & Other



Luminous Material


Luminous Locations

Hands, Markers

Power Reserve/Battery Life


Bezel Material


Bezel Action

120-Click Unidirectional

Lug Width


Maximum Bracelet/Strap Length


Case Height









Seiko Watches


Seiko Prospex Watches


Mens Watches

Free Strap Adjustment

It's important that your watch fits your wrist comfortably and looks great at the same time.

Leather strap watches tend to fit without a problem for most wearers. However, watches fitted with metal bracelets often need adjusting to get the perfect fit.

This is generally a very simple procedure. We can do this for you, or you can get the watch adjusted locally.

Option 1. Specify your wrist measurement and we will adjust it before being sent

When purchasing a watch which has a metal bracelet with adjustable links, we will gladly adjust the watch bracelet to fit your wrist before sending the watch to you - free of charge!

Simply type your wrist measurement (in inches or centimetres) into the bracelet size section of the checkout and we will ensure the watch bracelet is adjusted accordingly before being sent to you. We will include all the surplus links, with the watch.

How to measure your wrist

You can measure your wrist with a piece of string which you can measure against a ruler:

You should allow about half a centimetre (1/4 inch) of slack to prevent it being too tight on your wrist.

In the event of you needing an extra-long wrist bracelet, which requires an extension to the original watch, we must obtain extra links from the manufacturer, and in this event, we will contact you to inform you of any possible delays or applicable charges.

Watches with bracelets adjusted by WatchNation are still eligible under our refund policy.

Option 2. Buy the watch online from WatchNation and have it adjusted locally

If you wish, you can have it adjusted locally by another jeweller or key cutter. However, you will have to cover the cost of this option yourself.

Delivery Information

Selling Price Royal Mail 48 (Tracked) Royal Mail 24 (Tracked) Royal Mail Special Delivery by 1pm Royal Mail Special Delivery by 9am
£0 to £30 £2.95 £3.95 £5.95 £12.95
£30.01 to £50 FREE £2.95
£50.01 to £300 N/A FREE
£300.01 or more N/A FREE

All orders are sent using Royal Mail's tracked delivery service. Orders placed before 4.00 pm (Monday-Friday) or 11.00 am Saturday are dispatched the same day. Sunday orders are dispatched on the following Monday.

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On average, a delivery to the EU will take between 3-5 working days and delivery to the rest of the world will take 5-7 working days.


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