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 · EZM
Sinn EZM 41 mm Mother-of-pearl 18k
Reference 24871OR.39
Reference at a glance
- Brand
- Sinn
- Collection
- EZM
- Model
- Sinn EZM 41 mm Mother-of-pearl 18k
- Reference number
- 24871OR.39
- Year / era
- 1961 · 1960s — pre-quartz mechanical era
- Complication
- Minute repeater
- Movement
- Quartz
- Case material
- 18k yellow gold
- Dial type
- Mother-of-pearl
- Strap / bracelet
- Jubilee bracelet
- Water resistance
- 100 m
- Limited-edition status
- Regular production, not a limited edition
Case, dial & bracelet
- Case dimensions
- 41 mm
- Case thickness
- 8.1 mm
- Case material
- 18k yellow gold
- Bezel
- Fluted 18k gold
- Crystal
- Box sapphire with AR coating
- Dial
- Mother-of-pearl
- Hands
- Skeletonised sword hands, white luminescent
- Indexes
- Diamond-set hour markers
- Bracelet / strap
- Jubilee bracelet
- Clasp / buckle
- Triple-folding clasp with safety catch
- Water resistance
- 100 m
Movement
- Movement / calibre
- Calibre 86B — Quartz
- Movement type
- Manual-winding
- Frequency
- 36,000 vph (5 Hz)
- Power reserve
- 72 hours
- Number of jewels
- 25 jewels
- Complications
- Minute repeater
- Functions
- Perpetual calendar, leap year
- Watchmaker
- Assembled and regulated by a single watchmaker, who signs off the piece before casing.
Production & market
- Production period
- 1961 – 1969
- Limited-edition quantity
- Not applicable
- Current market information
- Trades close to retail on the secondary market, with steady demand for full-set examples.
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
Sinn EZM 41 mm Mother-of-pearl 18k sits within Sinn's EZM line, introduced in 1961. It carries the house codes established since 1961 — 18k yellow gold case, mother-of-pearl 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 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 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.