The New, Compact SPB313, SPB315 & SPB317 Are Seiko Prospex’s Thinnest Dive Watches (Live Pics & Price)

If Seiko‘s expertise in dive watches isn’t to be demonstrated anymore, there are a few comments that can be made about many of the older models released by the Japanese manufacturer, and that has mostly to do with the actual size of the cases. If you take for instance the most classic models, such as the Turtle and Samurai, or the King Turtle and King Samurai, we’re talking about 44mm or more. These are well-shaped, sure, but far from compact. Recently, however, the brand decided to go smaller, with compact 62MAS-inspired or 1968 Reinterpretation watches. And the trend continues with the new Seiko Prospex Automatic Diver 200m SPB313J1, SPB315J1 & SPB317J1, the thinnest dive watches in the range. 

Seiko’s history is packed with important watches, such as the 1965 62MAS (the brand’s first dive watch), the 1968 Hi-Beat Automatic Diver 300m and the 1970 Turtle watch. Seiko has long used these historical models to create modern watches reissuing vintage design cues. What we’re looking at today, with the new SPB313J1, SPB315J1 and SPB317J1, is again part of these models, with a design that feels rather retro-inspired, for a good reason. This model takes inspiration from a 1968 watch, the rather confidential 6105-8000 Automatic Diver, successor to the legendary 62MAS.

These new Seiko Prospex Automatic Diver 200m are mostly noticeable for their design and, importantly, their proportions. As said in the introduction, Seiko has decided for a couple of years now to downsize many of its dive watches, giving them far more wearable proportions and thus better ergonomics for daily use. An oversized watch can make sense for a professional diver when worn over a wetsuit… not so much with a linen shirt during a weekend. And since most of these watches will be worn on a daily basis or for leisure activities, reducing them is certainly a wise decision – at least, one we totally approve, here at MONOCHROME.

Back to the watches. All three models in this new range share the same specifications and case. As such, we’re talking about a late-1960s kind of case, with a cushion shape, straight and sharp casebands, and circular brushed surfaces on top. In typical Seiko style, the crown is positioned at 4 o’clock. And regarding the dimensions, these new SPB313J1, SPB315J1 and SPB317J1 measure 41mm in diameter, with a compact lug-to-lug measurement just below 47mm. And the best is the thickness, as these are the thinnest Prospex models, with 12.3mm in height. And on the wrist, it wears just perfectly. Nice balance between compactness and presence, without compromising the specifications.

The rest of the case feels classic, with a screw-down crown and a solid steel screwed caseback, both guaranteeing a comfortable 200-metre water-resistance. The top of the watch is protected by a sapphire crystal with internal anti-reflective coating and is framed by a unidirectional rotating bezel. The latter rotates on 120-clicks and features an aluminium insert, entirely graduated with a 60-minute scale.

As for the dial, no surprises, with a design that is shared with multiple other watches from the Prospex range, including the signature combination of applied markers and oversized luminous hands. In this version, the brand has opted for the retro “shovel” shaped hand with luminous and red tip and, in order to comply with the latest requirements of ISO standards, the date is placed at 4:30 so all markers can be luminous.

This new range of Prospex Automatic Diver is available in 3 different editions. First, there’s the highly classic SPB317J1, which features a grained matte black dial with silver-coloured accents on the dial and the bezel. This version is worn on a black, textured silicone strap. Next in line is the SPB313J1, with a matte white dial and dark-coated hands and markers. The bezel’s insert is black with a silver scale. Finally, there’s the SPB315J1, with a gilt-inspired colour scheme. The dial has a smooth texture and a very dark grey colour, while the markers, hands and diving scale are gold-coloured for a cool vintage touch. These two editions are worn on a flexible 5-link brushed steel bracelet with a folding clasp, push-buttons and diving extension.

Inside these compact cases is a well-known movement, the in-house calibre 6R35. Running at 3Hz and part of the brand’s mid-range portfolio of movement, it is mostly interesting due to its extended power reserve of 70 hours. The movement is hidden behind a closed caseback and, even though not mentioned to us, has a claimed accuracy of -15/+25 seconds per day – which we know to be a rather safe estimation.

The Seiko Prospex Automatic Diver 200m SPB313J1, SPB315J1 and SPB317J1 will soon be available from the brand’s boutiques and retailers, and are released as part of the permanent collection. Prices are EUR 950 for the SPB317J1 and EUR 1,150 for the SPB313J1 and SPB315J1. For more details, please visit www.seikowatches.com.