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 · 5 Sports
Seiko 5 Sports 36 mm Green 18k
Reference 78946OR.89
Reference at a glance
- Brand
- Seiko
- Collection
- 5 Sports
- Model
- Seiko 5 Sports 36 mm Green 18k
- Reference number
- 78946OR.89
- Year / era
- 1963 · 1960s — pre-quartz mechanical era
- Complication
- Moon phase
- Movement
- High-accuracy quartz
- Case material
- 18k rose gold
- Dial type
- Green sunburst
- Strap / bracelet
- Milanese mesh
- Water resistance
- 50 m
- Limited-edition status
- Limited edition of 50 pieces
Case, dial & bracelet
- Case dimensions
- 36 mm
- Case thickness
- 11.3 mm
- Case material
- 18k rose gold
- Bezel
- Smooth polished
- Crystal
- Anti-reflective sapphire, double-domed
- Dial
- Green sunburst
- Hands
- Mercedes hour hand with Chromalight display
- Indexes
- Applied Arabic numerals with luminous coating
- Bracelet / strap
- Milanese mesh
- Clasp / buckle
- Triple-folding clasp with safety catch
- Water resistance
- 50 m
Movement
- Movement / calibre
- Calibre 64A — High-accuracy quartz
- Movement type
- High-frequency automatic
- Frequency
- 28,800 vph (4 Hz)
- Power reserve
- 70 hours
- Number of jewels
- 27 jewels
- Complications
- Moon phase
- Functions
- GMT second time zone, date
- Watchmaker
- Finishing, assembly and timing are carried out in the manufacture's own atelier.
Production & market
- Production period
- 1963 – 1974
- Limited-edition quantity
- 50 pieces
- Current market information
- Consistently trades above retail; waiting lists at authorised dealers remain long.
Designer
In-house design studio
The reference was drawn by the manufacture's internal design office, where case, dial and movement architects work alongside the watchmakers rather than as an outside commission.
Historical significance
Seiko 5 Sports 36 mm Green 18k sits within Seiko's 5 Sports line, introduced in 1963. It carries the house codes established since 1881 — 18k rose gold case, green sunburst dial and high-accuracy quartz — and is one of the references collectors use to date the evolution of the collection.
Interesting facts
- The movement's bridges are decorated even where they will never be seen once the watch is cased.
- Early production dials show a slightly different minute track, and collectors pay a premium for them.
- The reference was originally planned as a one-year run and stayed in the catalogue for well over a decade.
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.