Seiko Prospex ‘King Turtle’ Automatic Blue Dial Black Silicone Strap Mens Watch SRPE07K1 

Product Code: SRPE07K1 Categories: , , ,

£420.00 Save £100.00 (19%)

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Seiko Prospex ‘King Turtle’ Automatic Blue Dial Black Silicone Strap Mens Watch SRPE07K1

This Seiko Prospex ‘King Turtle’ SRPE07K1 is based off one of the original Seiko diving watches, the 6309. It was nicknamed the ‘Turtle’ upon its release in 1976. The watch saw continued production for 12 years and has therefore become plentiful in the vintage watch market. The watch is so called due to the case of the piece calling similarities to a turtle shell.


This Seiko Prospex ‘King Turtle’ SRPE07K1 has a blue theme with a pattern which resembles the waves of the ocean. Next to the 8 o’clock position is a hidden shark fin which adds a small touch to this timepiece. Also, the end of the second hand resembles that of a sharks tail. This model in particular has been nicknamed the king turtle due to the upgrades that have taken place from the original. At the 3 o’clock position is a simplistic date window underneath a magnified window to allow for easy visibility at the depths of the ocean. Another upgrade is the Prospex logo at the middle of the dial which can be defined as an extreme sports family. Finally, a black silicone strap can be fastened using a standard buckle.


The movement on this model features 24 jewels which on the other hand is much better than the original 17 Jewels. The more jewels in a watch the better the accuracy is as it reduces friction and wear. The movement in particular used in this watch is a 4R36 which comes with a manual wind capacity and a duration of approximately 41 hours. The sapphire crystal glass has an anti-reflective coating which prevents glare from the sun or the torch of a diver. The indexes and hands are coated in LumiBrite which allow for easy visibility at night.
This watch has a water resistance of 200 metres, making it suitable for diving.

Key Features:

4R36 Calibre Automatic With Manual Wind 41 Hour Duration
Sapphire Crystal With Magnifier Anti-Reflective Coating LumiBrite
 Standard Buckle Push Button Release With Extender 200m Water Resistant
Thickness: 13.2mm Diameter: 45mm Length: 47.7mm
Screw Case Back Screw Down Crown Unidirectional Bezel
24 Jewels Day/Date Stop Second Hand Function

The Family: Prospex

Seiko Prospex challenges every limit, with a collection of timepieces for sports lovers and adventure seekers whether in the water, in the sky or on land. Seiko are constantly striving to bring ever greater reliability and safety to both professional and recreational divers. The variety in the collection offers different movements like automatic, solar, analogue quartz, solar chronograph and radio sync solar world time chronograph watches.

The Prospex Story:

Scuba-diving became increasingly popular around the 1960’s, an example of this was the formation of the Professional Association of Diving Instructors (PADI) in 1965. Moreover, diving equipment was becoming increasingly reliable, so more people began to dive recreationally. There was of course a crucial need for divers to be able to time their dives. Subsequently, the watch market responded to this necessity by flooding the market with reliable dive watches.

In 1965, Seiko first produced their original dive watch – the 6217. This was the very first Japanese dive watch and it paved the path for future divers that claim to meet Seiko’s Professional Specifications (the Prospex). The original 6217 was notably worn by the 8th Japanese Antarctic expedition. This model featured bidirectional rotating bezel, distinctive and lumed hands, and an easy-to-grip crown.

Although professional divers were still pining for a dive watch that had the capability of going deeper than 300 metres. The Seiko development team went about going to produce a watch which was capable of doing so. The year 1975 marks the release of the first Seiko Prospex, with the ability to be used in 600 metres of depth. It’s first diver watch to use a titanium case instead of a standard steel case. It was also the first to use a ceramic shroud for deep-sea diving and the first to use a hybrid analog digital watch with an alarm.

Another achievement for the Prospex family was the L-shape single crystal gasket, which prevented any helium escape valve uanessacry. This was one of the development teams first aims, to prevent a helium resistant watch. There were numerous other milestones that Seiko achieved with the Prospex. Such as in 1986 when Seiko produced a watch that was water resistant to 1000 metres.

The Brand: Seiko

Seiko’s story began in 1881 with the opening of a clock shop in Tokyo, it’s owner was Kintaro Hattori. Eleven years after the opening of his shop, Hattori opened a clock factory with ten employees and it was in 1895 that they began to produce pocket watches. Soon followed by alarm clocks in 1899, and then table clocks in 1902. Then in 1913 Hattori began working on his first wristwatch. The in 1924, 43 years after the initial opening, the brand Seiko was born with the creation of the first Seiko wristwatch.

Seiko established itself throughout the 20th century as being a driving force in the advancements that took place in the watching world. For example, in 1956, Seiko were the producers of the first winding wristwatch made in Japan. Then in 1964, Seiko became the official timer for the Tokyo Olympics. And then most notably Seiko unveiled the first quartz wristwatch, the Astron, in 1969. Marking the beginning of the quartz revolution. Or equally impressive the creation of the world’s first TV watch in 1982. And even more relevant today, with our abhorrent use of non-renewable energy sources, Seiko’s Kinetic. This watch had the ability to generate its own power from the movement of the wearer, it was released in 1988.

Ceaseless determination to innovate in every aspect of the watchmaker’s art is what defines Seiko’s 135-year history. By embracing this ethos, Seiko has been responsible for a string of industry-leading advances in the technology of time. Notably, the creation of the world’s first quartz watch in 1969. The listed technological developments serve as evidence to illustrate the revolutionary impact which Seiko has had on the watchmaking world. They are also markably unique in that they manufacture every aspect of every watch in-house.


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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

Cyclops Lens




Luminous Material


Luminous Locations

Hands, Markers

Power Reserve/Battery Life


Lug Width


Bracelet Type


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

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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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