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Sinn EZM 44 mm Green Sapphire
Sinn EZM 44 mm Green Sapphire — Front view

Front view

Dial, hands and bezel as delivered.

Case-back view

Case-back view

Case-back engraving and, where fitted, the sapphire display.

Movement

Movement

Calibre with its finishing and decoration.

On the wrist

On the wrist

Worn shot for proportion and strap drape.

Sinn · EZM

Sinn EZM 44 mm Green Sapphire

Reference 10368OR.78

Reference at a glance

Brand
Sinn
Collection
EZM
Model
Sinn EZM 44 mm Green Sapphire
Reference number
10368OR.78
Year / era
1999 · 1990s — mechanical revival
Complication
Flyback chronograph
Movement
Automatic COSC chronometer
Case material
Sapphire crystal case
Dial type
Green sunburst
Strap / bracelet
White rubber velcro strap
Water resistance
500 m
Limited-edition status
Regular production, not a limited edition
Compare this reference

Case, dial & bracelet

Case dimensions
44 mm
Case thickness
9.4 mm
Case material
Sapphire crystal case
Bezel
Fluted 18k gold
Crystal
Box sapphire with AR coating
Dial
Green sunburst
Hands
Mercedes hour hand with Chromalight display
Indexes
Applied Arabic numerals with luminous coating
Bracelet / strap
White rubber velcro strap
Clasp / buckle
Pin buckle in matching case metal
Water resistance
500 m

Movement

Movement / calibre
Calibre 52C — Automatic COSC chronometer
Movement type
Automatic with micro-rotor
Frequency
25,200 vph (3.5 Hz)
Power reserve
38 hours
Number of jewels
45 jewels
Complications
Flyback chronograph
Functions
Dive time, running seconds
Watchmaker
Finishing, assembly and timing are carried out in the manufacture's own atelier.

Production & market

Production period
1999 – 2002
Limited-edition quantity
Not applicable
Current market information
Thin secondary-market supply — pricing is set piece by piece at auction.

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 44 mm Green Sapphire sits within Sinn's EZM line, introduced in 1999. It carries the house codes established since 1961 — sapphire crystal case case, green sunburst dial and automatic cosc chronometer — and is one of the references collectors use to date the evolution of the collection.

Interesting facts

  • 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 movement's bridges are decorated even where they will never be seen once the watch is cased.
SI

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

  1. 1961

    Helmut Sinn founds Sinn in Germany.

  2. 1969

    The quartz era forces Sinn to redefine mechanical watchmaking.

  3. 1990

    Sinn enters the modern collector market with its signature lines.

  4. 2024

    Sinn continues to produce 556, 104, EZM and other icons in limited numbers.

More EZM