The Europe-Exclusive Seiko Prospex Alpinist Night Sky SPB531

One of the oldest Seiko watches still in production, the Alpinist was introduced in 1959 (note that the Laurel, released in 1913, is even more enduring), and it has since become a staple of the brand’s catalogue. Considered Seiko’s first professional watch, it was designed specifically by Seiko for Yama-Otoko, or mountain men. The collection returned in the 1990s with great success, including the cult-like SARB series. In recent years, the Seiko Prospex Alpinist made a strong comeback with its emblematic style and compass bezel, as well as purposeful GMT editions. In addition to a bunch of new Speedtimer models (including a Datsun-themed collection) released last week, fans of the Alpinist will be pleased with a new edition, the Prospex Alpinist Night Sky SPB531… For Europe only.

Let’s get straight to the point. There’s nothing spectacularly new about this Night Sky edition for Europe, other than the colour scheme. Is it bad? Not at all. The collection is, after all, a very appealing one as is. The new limited edition SPB531 is based on the classic SPB121 (and all its variants), with everything we’ve come to expect from this range of field/exploration watches. The watch measures 39.5mm in diameter by 13.2mm in thickness, and has a fairly controlled 46.4mm lug-to-lug measurement. Made of steel, with brushed and polished surfaces, its main distinction is the presence of an additional crown at 4 o’clock, which actuates an internal rotating bezel with a compass. Other specs are classic: screw-down crown, sapphire crystal with AR coating and solid 200m water-resistance.

What sets this Europe-only limited edition SPB531 apart from the rest of the collection is its dial and colours, which are said to be inspired by “the night sky over the mountains” – hence its “Night Sky” nickname. Subtly brushed, the dark blue dial is paired with classic applied hour markers – numerals for even numbers and triangles for the rest – as well as luminous cathedral-style hours and minutes hands. The seconds hand is gold-toned for a warmer effect. The display includes hours, minutes, seconds (hacking) and a date window under a magnifying glass, with a black disc.

Inside the case and visible under a see-through caseback (screwed) is the in-house calibre 6R35, an automatic movement with a 70h power reserve. The Prospex Alpinist Night Sky SPB531 is delivered with two straps in a special edition box: a navy blue leather strap with crocodile embossing and a textured blue nylon strap. Both come equipped with a three-fold clasp in steel, and the lug width is a practical 20mm.

A limited edition of 3,000 pieces available exclusively in Europe (UK included), Seiko Prospex Alpinist Night Sky SPB531 will be available as of September 2025 and priced at EUR 890, GBP 780 or CHF 930. For more details, please consult seikowatches.com.