Seiko Astron SSH185J1 — GPS Solar Chronograph 2025 Limited Edition

The Seiko Astron SSH185J1 is one of only 1,200 pieces produced worldwide — the rarest of the 2025 Seiko Astron limited editions, and the most technically and materially distinctive. Created under the "Solidity" design theme that symbolises Seiko's innovative spirit since 1881, the SSH185J1 introduces two design elements never before seen in this series: a ceramic and titanium bracelet in black and white, and green-accented subdials on a black horizontal line-patterned dial. Featuring dual-time capability alongside a 1/20th of a second GPS solar chronograph, it is a timepiece of extraordinary specification and unmistakable character.

The black textured dial features a horizontal line-patterned solar cell and a vertical subdial layout — the subdial at 12 o'clock for the chronograph function, at 9 o'clock for setting modes, and at 6 o'clock for dual time — each accented in green for a purposeful, technical aesthetic that references the precision instrumentation of motorsport and aviation. The super-hard coated titanium case with aluminium and ceramic bezel sits at 43.4mm with a power reserve indicator and an almost seamless flow from case through lugs to the five-piece ceramic and titanium bracelet — designed with a low centre of gravity for all-day comfort and micro-adjustable for a personalised fit.

Key Features

• Seiko 5X83 GPS solar movement — pinpoints your exact time zone by receiving signals from 4 or more GPS satellites
• Accuracy: ±1 second every 100,000 years with daily automatic GPS time adjustment — the most accurate wristwatch technology available
• 1/20th of a second chronograph — measures elapsed time up to 12 hours with exceptional precision
• Dual time capability — bottom subdial adjustable to a second time zone; main hands manually adjustable to different time zones
• Perpetual calendar — automatically adjusts for short months and leap years until February 2100
• Day-date display — full calendar functionality built in
• Approx. 6-month power reserve at full charge; approx. 2-year power save reserve — exceptional solar efficiency
• Power reserve indicator — monitor remaining charge at a glance
• Green-accented vertical subdial layout — purposeful technical aesthetic on a horizontal line-patterned black dial
• Subdial at 12 o'clock for chronograph; subdial at 9 o'clock for setting modes; subdial at 6 o'clock for dual time
• Ceramic and titanium bracelet in black and white — unique bracelet material combination in the Astron limited edition series
• Low centre of gravity bracelet design — engineered for all-day wrist comfort
• Micro-adjustable clasp — personalised fit with incremental adjustment
• Aluminium and ceramic bezel — layered material construction for durability and design depth
• Super-hard coated titanium case at 43.4mm — lightweight, strong, and exceptionally durable
• Dual-curved sapphire crystal with super clear coating — premium scratch resistance and superior optical clarity
• AM/PM indicator — clear 12-hour cycle reference
• Lumibrite on hands and markers — superior low-light legibility
• 100M water resistance — swim-ready and built for active lifestyles
• Limited edition — only 1,200 pieces produced worldwide — the rarest of the 2025 Astron limited editions

Why You'll Love It

The SSH185J1 is the most materially sophisticated and rarest of the 2025 Seiko Astron limited editions — and the green-accented subdials are the detail that collectors will remember. Where the Spiral Galaxy models (SSJ039J1 and SSH187J1) lead with dial artistry and the SSJ037J1 leads with architectural case innovation, the SSH185J1 leads with material depth: ceramic and titanium in the bracelet, aluminium and ceramic in the bezel, super-hard coated titanium in the case — three distinct materials working together in a single coherent design. The green accents on the subdials give the black dial a technical character that references precision instruments without being aggressive or loud. The 5X83 GPS solar calibre with its 1/20th of a second chronograph, dual time, and perpetual calendar running to 2100 means the specification is every bit as sophisticated as the materials. With only 1,200 pieces worldwide — 300 fewer than the next rarest Astron limited edition in this series — the SSH185J1 is genuinely the hardest to find.

SSH185J1 vs SSH187J1 — Astron GPS Solar Chronograph Comparison

Both models use the same 5X83 GPS solar chronograph calibre with identical functions — GPS accuracy, 1/20th second chronograph, dual time, perpetual calendar, day-date, and Lumibrite. The differences are in design and rarity. The SSH187J1 has the Spiral Galaxy turquoise blue dial with 1,500 pieces — bold, cosmic, and visually dramatic. The SSH185J1 has a black dial with green-accented subdials and a ceramic and titanium bracelet — 1,200 pieces, more technical in character, and the rarer of the two. Both share the same movement capability. The choice comes down to whether you want a watch that leads with its dial art or one that leads with its material engineering.

The Seiko Astron Story

Seiko Astron is the world's first GPS solar watch — powered by light and automatically adjusted to your exact time zone through satellite technology. The story begins in 1881, when Kintaro Hattori founded a clock and watch shop in Ginza, Tokyo — the business that would become the Seiko of today. Since the first Astron was introduced in 1969 as the world's first quartz watch, Seiko has continuously pushed the boundaries of what a wristwatch can do. The GPS Solar Astron, launched in 2012, represented a new frontier — a watch that never needs setting, never runs out of power in normal use, and is accurate to a standard no mechanical or conventional quartz watch can match. The SSH185J1 carries that spirit of innovation forward in 2025 with a design built from the most advanced materials available to the collection.

Backed by Seiko's official warranty. Authentic Seiko Astron limited edition watch, sold by authorised retailer City Chain Singapore.

Also available: Spiral Galaxy chronograph — shop the SSH187J1, Spiral Galaxy 3-hand — shop the SSJ039J1, and 2025 architectural edition — shop the SSJ037J1. Explore the full Seiko Astron Collection or browse all Seiko watches at City Chain Singapore.