Monochrome Watches
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The Seiko Prospex Land “Tortoise” Collection

The Seiko Turtle that transformed into an exploration watch.

| By Brice Goulard | 5 min read |
Seiko Prospex Land Tortoise - SRPG13K1 SRPG15K1 SRPG17K1 SRPG18K1

How do you call a turtle that is exclusively land-dwelling…? A tortoise. How do you call a Seiko Turtle that is intended for land exploration, and not for diving activities? Well, easy, a Seiko Tortoise. See, that’s how simple the story behind most of Seiko’s nicknames is. So, as soon as we’ve heard about Seiko’s new take on the Turtle, equipped with a compass bezel instead of a classic 60-minute scale, the name Tortoise immediately surfaced too. After a short introducing article a couple of weeks ago, we had the chance to get the watches at the office, so it’s time for a hands-on session with this new Seiko Prospex Land “Tortoise” models SRPG13K1, SRPG15K1, SRPG17K1 and SRPG18K1. 

The name Turtle at Seiko refers to more than just a watch, but to an entire line of watches with a specific design. And they cover the entire range of prices at Seiko too. Basically, it comes down to all the diver’s models inspired by the famous reference 6105-8110, a watch mostly known for two things. One, being on the wrist of explorer Naomi Uemura when he achieved his dog-sledge run from Greenland to Alaska. And also, for being the watch of Captain Willard, portrayed by Martin Sheen, in the iconic movie Apocalypse Now. The Seiko 6105 was a sturdy dive watch with a water resistance of 150 metres. What caught everybody’s eye was the crown positioned at 4 o’clock and the highly protected case that looked like the shell of a turtle. And if you look at recent years, this is a design that has been used, among others, in the accessible Prospex SRP series, the Willard-reissues SPB151 and SPB153, in the recent SLA049 and SLA051, and on top of the range on the SLA033. And all were dive watches.

Seiko Prospex Land Tortoise - SRPG13K1 SRPG15K1 SRPG17K1 SRPG18K1

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But today’s models, as somehow indicated by their nickname Tortoise, are not intended to go take a jump deep under the sea. Or at least, they will lack one precise function for this… because otherwise, these watches could be fairly capable diver’s pieces.

The reason for calling these references SRPG13K1, SRPG15K1, SRPG17K1 and SRPG18K1 the “Seiko Tortoise” is simple: they share their case design with many other “Turtle” diving watches of the brand. All in all, they have this typical pebble-shaped case without protruding lugs, with strong shoulders and an overall soft and circular shape. And, of course, there’s the crown positioned at 4 o’clock, which enhance the comfort. But an important thing to note is about proportions. These watches are indeed close in shape to the Prospex SRP series, but not in size. We’re not talking 45mm diameter, but a case that is only 42.4mm wide. You could argue that this is large, but do keep in mind that Turtle/Tortoise watches wear smaller than expected, with here a lug-to-lug measurement of only 45mm. And that is fairly compact.

As I already explained with the Alpinist series, I’m very pleased to see Seiko downsizing most of its sports watches, coming back to more “down to earth” dimensions. The Turtle SRP Series was indeed borderline oversized and these new Tortoise models are fairly compact on the wrist despite having the presence and robustness you expect from a Prospex model. And at 11.7mm in height, these watches aren’t even thick! Finally, more compact doesn’t mean less performing, as these are equipped with a screw-down crown and caseback, and can withstand depths up to 200m. Not bad for a land-oriented model.

Seiko Prospex Land Tortoise - SRPG13K1 SRPG15K1 SRPG17K1 SRPG18K1

The most obvious difference with a classic Turtle model is the bezel. Indeed, framing the sapphire crystal is a bidirectional bezel (difference 1), equipped with an anodized aluminium insert printed with a compass scale (difference 2). And while the use of such a scale is always debatable in terms of accuracy compared to a real compass, they bring a cool touch to this Seiko Tortoise collection, specifically when the insert is two-tone. The back of the watch is also specific, as engraved with “ground-to-air emergency signal” codes – even though we hope that you’ll never have to use these codes while wearing your watch…

Seiko Prospex Land Tortoise - SRPG13K1 SRPG15K1 SRPG17K1 SRPG18K1

As for the dial, we can see some familiar traits, yet once again these Tortoise models have their own set of hands and indexes, different from what’s usually found on diving-oriented watches. Whether the large applied indexes, the arrow-shaped hour hand (the most important as working in conjunction with the compass bezel, while on a dive watch the minute hand is crucial), the baton minute or the seconds hand with lollipop counterweight, are all filled generously with Seiko’s ultra-efficient LumiBrite material. A date is positioned at 4:30, which will certainly create some discussions…

Seiko Prospex Land Tortoise - SRPG13K1 SRPG15K1 SRPG17K1 SRPG18K1

The Seiko Prospex Land “Tortoise” Collection comprises 4 watches. First is the SRPG13K1, which is certainly the most striking edition in this collection, thanks to its earthy colour scheme, combining a light khaki/beige dial and a green/beige bezel. It is worn on a green fabric strap. Then comes a slightly more classic edition, the SRPG15K1, with a dark blue dial, a grey and blue bezel and a blue fabric strap. The two other models are slightly more formal in style. The SRPG17K1 has a black dial with gilded indexes/hands and a gold-coloured scale on its bezel. The SRPG18K1 pushed this formal attire even further, with its gold PVD coated case and brown dial/bezel. Both are worn on a leather strap.

As for the mechanics, these Tortoise models rely on a tried-and-tested automatic movement, the classic entry-level calibre 4R35, which is found in many ranges, such as Presage Cocktail watches, the Samurai or the King Turtle – with date or day-date function. Running at 3Hz, it boasts 41 hours of power reserve and features a stop-seconds.

Seiko Prospex Land Tortoise - SRPG13K1 SRPG15K1 SRPG17K1 SRPG18K1

Overall, we’re talking about cool, nicely designed, well proportioned and robust sports watches here. Surely, these Tortoise watches are not proper diving models, due to the lack of a 60-minute scale, but they can still withstand some underwater action. Also, the compass bezel is more of a design statement than something that will be often used. But, all in all, these are great summer watches ready for all-terrain adventure.

Availability & Price

The Seiko Prospex Land “Tortoise” Collection will be available in May 2021 from retailers worldwide, and part of the permanent collection. The SRPG13K1, SRPG15K1 and SRPG17K1 are all priced at EUR 540, while the gold PVD-coated model SRPG18K1 will retail for EUR 590.

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7 responses

  1. Smaller size and date window at 4:30 are real improvements that I hope Seiko will also bring to new Turtles.

  2. I’m loving the new sizes of Seiko! Hopefully they do an 11mm samurai. I’d be all over that!

  3. I wish every review had the lug width. Why is it always lacking?

  4. What’s the difference between the srpg17k1 and the srph17k1… is it just the bracelet?

  5. @L – The difference is indeed the steel bracelet (SRPH17K1) vs. the textile strap (SRPG17K1), but also some details of the dial, as the SRPG17K1 has gold-coloured hands, markers, and bezel scale, while the SRPH17K1 has silver-coloured accents.


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