Front view
Dial, hands and bezel as delivered.
Case-back view
Case-back engraving and, where fitted, the sapphire display.
Movement
Calibre with its finishing and decoration.
On the wrist
Worn shot for proportion and strap drape.
Seiko · Prospex
Seiko Prospex 36 mm Green Stainless
Reference 56165ST.15
Reference at a glance
- Brand
- Seiko
- Collection
- Prospex
- Model
- Seiko Prospex 36 mm Green Stainless
- Reference number
- 56165ST.15
- Year / era
- 1952 · 1950s — pre-quartz mechanical era
- Complication
- Flyback chronograph
- Movement
- Eco-Drive solar quartz
- Case material
- Stainless steel
- Dial type
- Green sunburst
- Strap / bracelet
- Integrated steel bracelet
- Water resistance
- 50 m
- Limited-edition status
- Regular production, not a limited edition
Case, dial & bracelet
- Case dimensions
- 36 mm
- Case thickness
- 9.4 mm
- Case material
- Stainless steel
- Bezel
- Smooth polished
- Crystal
- Anti-reflective sapphire, double-domed
- Dial
- Green sunburst
- Hands
- Faceted dauphine hands, polished by hand
- Indexes
- Printed minute track with applied batons
- Bracelet / strap
- Integrated steel bracelet
- Clasp / buckle
- Folding clasp in matching case metal
- Water resistance
- 50 m
Movement
- Movement / calibre
- Calibre 15F — Eco-Drive solar quartz
- Movement type
- Automatic with micro-rotor
- Frequency
- 28,800 vph (4 Hz)
- Power reserve
- 72 hours
- Number of jewels
- 33 jewels
- Complications
- Flyback chronograph
- Functions
- Flying tourbillon, power reserve
- Watchmaker
- The calibre is built in-house and adjusted in five positions before delivery.
Production & market
- Production period
- 1952 – 1960
- Limited-edition quantity
- Not applicable
- Current market information
- Values have stabilised after the 2022 correction; condition and box-and-papers drive the premium.
Designer
Marc Newson
Marc Newson is an Australian industrial designer whose work spans Qantas cabins, Apple hardware and Jaeger-LeCoultre's Atmos clocks; his watch design reduces the object to pure geometry and legibility.
Historical significance
Seiko Prospex 36 mm Green Stainless sits within Seiko's Prospex line, introduced in 1952. It carries the house codes established since 1881 — stainless steel case, green sunburst dial and eco-drive solar quartz — and is one of the references collectors use to date the evolution of the collection.
Interesting facts
- Early production dials show a slightly different minute track, and collectors pay a premium for them.
The House
Seiko
Brand facts
- Founding year
- 1881
- Founder
- Kintaro Hattori
- Headquarters
- Japan
- Tier
- Japanese
- Major collections
- Prospex, Presage, King Seiko, Astron, 5 Sports
- Signature technologies
- In-house hairspring production · Proprietary case-hardening and polishing · Hand-applied guilloché dials
- Famous movements
- Eco-Drive solar quartz · High-accuracy quartz · Spring Drive · Automatic, 24 jewels
- Notable watches
- Seiko Prospex 36 mm Green Stainless (1952) · Seiko Prospex 38 mm Black 18k (1977) · Seiko Prospex 38 mm Meteorite Platinum (1972) · Seiko Prospex 42 mm Green Sapphire (1997)
Brand history
Seiko has spent more than 145 years refining a single idea: a watch should outlive its owner. From the earliest workshop pieces to today's Prospex, the house has balanced technical ambition with a recognisable design language, and its collections remain among the most closely followed by collectors worldwide.
Kintaro Hattori established Seiko in 1881, working from Japan at a time when precision was measured by hand. The founder's obsession with finishing and accuracy still defines every Seiko calibre produced today.
Historical milestones
1881
Kintaro Hattori founds Seiko in Japan.
1899
Seiko earns its first international recognition for precision timekeeping.
1969
The quartz era forces Seiko to redefine mechanical watchmaking.
1990
Seiko enters the modern collector market with its signature lines.
2024
Seiko continues to produce Prospex, Presage, King Seiko and other icons in limited numbers.