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The Seiko Prospex Diver GMT Arctic Ocean SPB439

A new limited edition part of the "Save the Ocean" Series, with a cool glacier-like dial.

| By Brice Goulard | 4 min read |
Seiko Prospex Diver GMT Arctic Ocean SPB439

Black Series, PADI editions, Save the Ocean… While the Prospex collection by Seiko is already wide (to say the least), it also includes themed sub-series. The “Save the Ocean” models are some of the most attractive ones, adding a touch of originality to classic models, as well as benefitting a good cause. Following the recent release of Seiko’s first-ever GMT-equipped mechanical dive watch, the brand released the ice-blue SPB385 Save the Ocean limited edition. A successful combination of functions and an attractive design, which is now used again with this new reference, the Prospex Diver GMT Arctic Ocean SPB439.

The combination of a dive watch with a GMT complication makes for some of the most attractive and practical watches. Go-anywhere, do-anything watches. Surprisingly, this specific combo, at least in mechanical formats, first appeared at Seiko only last year, with the introduction of the references SPB381 and SPB383. A natural evolution as GMT watches are currently the big thing for Seiko, as we also found this function in the Alpinist collection, as well as in the accessible Seiko 5 Sports range. The launch of Seiko’s first mechanical GMT diver was, however, not done with two but three watches, the last one being a Save the Ocean limited edition, the SPB385 – an attractive model with a textured ice blue dial, presented with a steel bracelet and a cool braided strap in recycled polyester.

Seiko Prospex Diver GMT Arctic Ocean SPB439
Above, the new Prospex Diver GMT Arctic Ocean SPB439 – below, the Save the Ocean SPB385 uses the same technical base, and the SPB333 uses the same style for the dial.

Using the same technical base and mixing it with the look of yet another Save the Ocean limited edition – the SPB333, a.k.a the baby White Birch – we now have this new reference… and it does look quite stunning too. Starting with the specifications and the case, the new Arctic Ocean SPB439 is, on most parts, identical to the 3 other GMT divers. As such, it comes with a case inspired by a dive watch released by the brand in 1968, the reference 6159-7001, and is closely related to the no-GMT SPB185 and SPB187. Angular and powerful, with strong lugs and faceted sides, it is a watch with presence and respectable dimensions. At 42mm in diameter and 48.6mm in length, it is not what you’ll call a compact watch. But it remains pleasant and comfortable, as its non-limited siblings.

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Seiko Prospex Diver GMT Arctic Ocean SPB439

The addition of a traveller’s complication doesn’t affect the diving credentials of this watch. The fact that Seiko chose to keep a 60-minute scale on the bezel, and not a 24-hour GMT scale, shows that it is meant to be a diver’s watch first, with the addition of a GMT function. A relatively rare sight at Seiko, this unidirectional bezel is equipped with a ceramic insert – here in glossy black with a white track. With its solid steel back and screw-down crown, it retains a comfortable 200m water-resistance and the dial is protected by a domed and bevelled sapphire crystal with an anti-reflective coating.

Seiko Prospex Diver GMT Arctic Ocean SPB439

New to this limited edition is the dial, which now uses a more classic silver-white colour instead of the more pronounced light blue used in the previous version. The Prospex Diver GMT ref. SPB439, as such, comes closer to the SPB333 and its glacier-inspired dial. Despite this light colour, also used on the embossed markers, there’s a fairly decent amount of contrast on this dial and all indications appear clear and generously coated in LumiBrite. On a personal note, I’ve always had a soft spot for white-dialed dive watches and the addition of this icy texture is surely appealing to me. The other specificity of this version are the light blue accents, found on the GMT hand and inscription, as well as the 24-hour scale on the inner flange.

Inside the SPB439 is the now well-known calibre 6R54, an office-like GMT automatic engine running at 3Hz and storing a comfortable 72-hour power reserve. While I’d certainly prefer a flyer-like complication (see here to understand the difference), it remains a nice feature and makes for a rather complete watch.

Seiko Prospex Diver GMT Arctic Ocean SPB439

Worn on a 3-link brushed bracelet with a three-fold clasp, secure lock and diving extension, this Seiko Prospex Diver GMT Arctic Ocean SPB439 is a limited edition of 1,500 pieces. It is priced at EUR 1,800 and is now available from the brand’s boutiques and selected retailers. Also, a proportion of proceeds from this timepiece will be given back to the PADI and PADI Aware Foundation’s Marine Debris Program to rid the ocean of marine debris.

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3 responses

  1. This is quite pricey at 1800 euros for a 6R movement, imo. As usual these days, Seiko’s prices are a little too ambitious to say the least – especially the limited editions.

  2. Perhaps it is Seiko’s strategy to confuse the buyer regarding price and value? When I look at this watch I think ‘Oh, a GMT Marinemaster with a white dial for 1800 Euros? Great deal’.

    I fancied the MM ten years ago when it was praised as amazing value. But since then I have lost track of all the different Seiko models.

    I am aware that this is not an MM.

  3. I’d rather get a micro-brand utilizing the Citizen 9075 movement…own three of these from different manufacturers and were all obtained under 1000USD and accuracy was withing COSC on all of them as I measured. The Seiko 6Rs aren’t even regulated I feel.

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