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.
Sinn · 903
Sinn 903 39 mm Blue Quartz
Reference 68732OR.35
Reference at a glance
- Brand
- Sinn
- Collection
- 903
- Model
- Sinn 903 39 mm Blue Quartz
- Reference number
- 68732OR.35
- Year / era
- 1991 · 1990s — mechanical revival
- Complication
- Time and date
- Movement
- Quartz
- Case material
- Quartz TPT
- Dial type
- Blue "Grande Tapisserie"
- Strap / bracelet
- NATO textile strap
- Water resistance
- 300 m
- Limited-edition status
- Limited edition of 188 pieces
Case, dial & bracelet
- Case dimensions
- 39 mm
- Case thickness
- 8.1 mm
- Case material
- Quartz TPT
- Bezel
- Unidirectional ceramic 60-minute
- Crystal
- Anti-reflective sapphire, double-domed
- Dial
- Blue "Grande Tapisserie"
- Hands
- Faceted dauphine hands, polished by hand
- Indexes
- Printed minute track with applied batons
- Bracelet / strap
- NATO textile strap
- Clasp / buckle
- Titanium deployant clasp
- Water resistance
- 300 m
Movement
- Movement / calibre
- Calibre 4A — Quartz
- Movement type
- Manual-winding
- Frequency
- 36,000 vph (5 Hz)
- Power reserve
- 10 days
- Number of jewels
- 31 jewels
- Complications
- Time and date
- Functions
- Dive time, running seconds
- Watchmaker
- The calibre is built in-house and adjusted in five positions before delivery.
Production & market
- Production period
- 1991 – 2002
- Limited-edition quantity
- 188 pieces
- Current market information
- Consistently trades above retail; waiting lists at authorised dealers remain long.
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
Sinn 903 39 mm Blue Quartz sits within Sinn's 903 line, introduced in 1991. It carries the house codes established since 1961 — quartz tpt case, blue "grande tapisserie" dial and quartz — and is one of the references collectors use to date the evolution of the collection.
Interesting facts
- The reference was originally planned as a one-year run and stayed in the catalogue for well over a decade.
- The case is finished by hand, alternating polished and satin-brushed surfaces in a single pass so the edges stay razor sharp.
- Early production dials show a slightly different minute track, and collectors pay a premium for them.
The House
Sinn
Brand facts
- Founding year
- 1961
- Founder
- Helmut Sinn
- Headquarters
- Germany
- Tier
- Affordable & Tool Watches
- Major collections
- 556, 104, EZM, U1, 903, Hydro
- Signature technologies
- Anti-magnetic silicon escapement · Shock-absorbing movement mounting
- Famous movements
- Automatic, 38-hour reserve · Automatic Powermatic 80 · Automatic COSC chronometer · Quartz
- Notable watches
- Sinn 556 42 mm Silvered 18k (1975) · Sinn 556 43 mm Slate Sapphire (1961) · Sinn 556 36 mm Mother-of-pearl 18k (1976) · Sinn 556 43 mm Ice 18k (1965)
Brand history
Sinn has spent more than 65 years refining a single idea: a watch should outlive its owner. From the earliest workshop pieces to today's 556, the house has balanced technical ambition with a recognisable design language, and its collections remain among the most closely followed by collectors worldwide.
Helmut Sinn established Sinn in 1961, working from Germany at a time when precision was measured by hand. The founder's obsession with finishing and accuracy still defines every Sinn calibre produced today.
Historical milestones
1961
Helmut Sinn founds Sinn in Germany.
1969
The quartz era forces Sinn to redefine mechanical watchmaking.
1990
Sinn enters the modern collector market with its signature lines.
2024
Sinn continues to produce 556, 104, EZM and other icons in limited numbers.