SEIKO PROSPEX SPB121J1 ALPINIST AUTOMATIC MEN WATCH

Seiko Prospex SPB121J1 — Alpinist Automatic Watch

The Seiko Prospex SPB121J1 Alpinist is a modern expression of one of the most enduring designs in Japanese watchmaking history — a field and mountain watch first conceived in 1959 for Japan's alpine enthusiasts and refined across sixty-five years without ever departing from the essentials that made it iconic. The green dial, brown leather strap, and inner compass ring have defined the Alpinist from the original to the current SPB121J1, and the combination remains as functionally purposeful and aesthetically distinctive today as it was when Seiko's mountain climbers first took it into the field.

Powered by the in-house 6R35 automatic calibre with hand-winding capability and a 70-hour power reserve, the SPB121J1 delivers reliable everyday performance at +25/-15 seconds per day. The sapphire crystal protects the green dial through active daily use and field conditions. Lumibrite on the hands and hour markers ensures readability at dawn and in low light — the conditions that alpinists and early starters encounter most frequently. The inner compass ring is independently rotatable for bearing reference in the field, and the 39.5mm silver stainless steel case at 13.2mm slim wears with the compact, purposeful character that the Alpinist has always embodied.

Key Features

• Seiko 6R35 automatic movement with manual winding — self-winding with the convenience of hand-winding when needed
• Approx. 70-hour power reserve — reliable performance through extended field use without wearing
• Accuracy: +25/-15 seconds per day — dependable automatic timekeeping
• 200M water resistance — robust protection for outdoor and water activities
• Green dial with baton markers — the defining Alpinist colourway since 1959
• Lumibrite on hands and hour markers — superior legibility in low light and pre-dawn conditions
• Inner compass ring — independently rotatable bearing reference for navigation in the field
• Sapphire crystal — premium scratch resistance and superior optical clarity
• 39.5mm silver stainless steel case — compact field watch proportions at 13.2mm slim profile
• Screw-down crown — weather-resistant protection for field use
• Date display — everyday practicality built in
• Brown leather strap — classic field watch aesthetic, comfortable for extended daily wear

Why You'll Love It

The SPB121J1 is the Alpinist for those who want the classic green dial and brown leather combination in the most directly accessible form — a watch that carries sixty-five years of design heritage without requiring a premium price. The green dial is one of the most immediately recognisable in the entire Seiko Prospex lineup, the brown leather strap gives it a natural, field-ready character that works from mountain trail to business casual, and the inner compass ring is a functional navigation reference that no other Seiko design shares in the same way. The 6R35 calibre's 70-hour reserve handles any extended weekend, the sapphire crystal keeps the green dial pristine, and the 39.5mm case wears with a compact authority that makes it one of the most versatile watches in the Prospex family.

About the Seiko Alpinist

The Seiko Alpinist was born in 1959 — a watch designed for Japan's mountain climbers at a time when domestic watchmaking was finding its identity in extreme environments. The original Alpinist established the inner compass ring, the green dial, and the compact case proportions that define every Alpinist to this day. Over sixty-five years the design has been refined but never fundamentally altered, because the original solved the problem it was designed for with precision and elegance. The SPB121J1 carries that story forward in its most enduring expression.

The Seiko Prospex Story

Prospex is a combination of the words "Professional" and "Specifications." Seiko Prospex timepieces are designed to be practical, reliable, and durable — built to meet the high standards required in extreme environments for sports lovers and adventure seekers alike. 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. The Alpinist has been part of the Prospex story since before the Prospex name existed — a mountain watch that predates the dive watch, the field watch, and the GPS solar by decades. The SPB121J1 carries that sixty-five year legacy forward.

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

Also available in the Alpinist family: Alpinist GMT — SPB379J1. Explore the full Seiko Prospex Collection or browse all Seiko watches at City Chain Singapore.