Seiko’s New Prospex Alpinist Takes Cue From the “Night Sky”

Summary

  • Seiko’s Night Sky Alpinist SPB531J1 is a European-exclusive limited edition set to release in September
  • Housed in a 39.5 mm steel case, the watch features dual crowns, a midnight-blue dial and lume-filled cathedral hands

Following a joint launch of three Speedtimers watches with Datsun, Seiko introduces a unique, limited-edition Prospex Alpinist model, available only in the European market. Named “Night Sky,” this watch carries the reference number SPB531J1. Inspired by the dark, starry skies over alpine mountains, it pays homage to the original 1959 Alpinist designed for Japanese mountain guides while giving a contemporary twist for today’s adventurers.

At its core is a 39.5 mm stainless-steel case, characterized by prominent crown guards and a dual-crown design. The midnight blue dial showcases a subtle vertical brushing, dark gray numbers, hands filled with luminescent material in the shape of cathedrals, and a date window magnified by Cyclops at 3 o’clock. Through the transparent caseback, viewers can appreciate Seiko’s self-winding 6R35 movement, offering a 70-hour power reserve and precision within -15/+25 seconds per day, along with a stop-seconds function.

3,000 units of the Seiko Prospex Alpinist “Night Sky” are now available for inquiry on Seiko’s UK webstore, with a planned release date in September. The watch is priced at approximately £780 GBP ($1,025 USD) upon its release.

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2025-08-02 06:55