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Longines Legend Diver 40 mm Skeletonised 18k
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.

Longines · Legend Diver

Longines Legend Diver 40 mm Skeletonised 18k

Reference 73624OR.26

Reference at a glance

Brand
Longines
Collection
Legend Diver
Model
Longines Legend Diver 40 mm Skeletonised 18k
Reference number
73624OR.26
Year / era
1963 · 1960s — pre-quartz mechanical era
Complication
Time only
Movement
Spring Drive
Case material
18k rose gold
Dial type
Skeletonised
Strap / bracelet
Milanese mesh
Water resistance
30 m
Limited-edition status
Regular production, not a limited edition
Compare this reference

Case, dial & bracelet

Case dimensions
40 mm
Case thickness
8.8 mm
Case material
18k rose gold
Bezel
Octagonal with 8 hexagonal screws
Crystal
Box sapphire with AR coating
Dial
Skeletonised
Hands
Blued steel Breguet-style hands
Indexes
Applied Arabic numerals with luminous coating
Bracelet / strap
Milanese mesh
Clasp / buckle
Pin buckle in matching case metal
Water resistance
30 m

Movement

Movement / calibre
Calibre 40B — Spring Drive
Movement type
Automatic with micro-rotor
Frequency
28,800 vph (4 Hz)
Power reserve
55 hours
Number of jewels
40 jewels
Complications
Time only
Functions
Dive time, running seconds
Watchmaker
The calibre is built in-house and adjusted in five positions before delivery.

Production & market

Production period
1963 – 1967
Limited-edition quantity
Not applicable
Current market information
Thin secondary-market supply — pricing is set piece by piece at auction.

Designer

Emmanuel Gueit

Emmanuel Gueit came from a family of Geneva jewellers and was barely into his twenties when he drew the oversized Royal Oak Offshore in 1993 — a watch the house's traditionalists resisted and collectors turned into an icon.

Historical significance

Longines Legend Diver 40 mm Skeletonised 18k sits within Longines's Legend Diver line, introduced in 1963. It carries the house codes established since 1832 — 18k rose gold case, skeletonised dial and spring drive — 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 bracelet tapers across its length, which is why the profile looks thinner on the wrist than the specification suggests.
LO

The House

Longines

Brand facts

Founding year
1832
Founder
Auguste Agassiz
Headquarters
Switzerland
Tier
Premium
Major collections
Master Collection, HydroConquest, Spirit, Legend Diver, DolceVita, Conquest
Signature technologies
Proprietary case-hardening and polishing · Shock-absorbing movement mounting · In-house hairspring production
Famous movements
High-beat automatic · Automatic chronograph · Automatic, Swiss lever escapement · Spring Drive
Notable watches
Longines Master Collection 44 mm Green Ceramic (1974) · Longines Master Collection 40 mm Meteorite 18k (1964) · Longines Master Collection 41 mm Black 18k (1998) · Longines Master Collection 44 mm Skeletonised Sapphire (1969)

Brand history

Longines has spent more than 194 years refining a single idea: a watch should outlive its owner. From the earliest workshop pieces to today's Master Collection, the house has balanced technical ambition with a recognisable design language, and its collections remain among the most closely followed by collectors worldwide.

Auguste Agassiz established Longines in 1832, working from Switzerland at a time when precision was measured by hand. The founder's obsession with finishing and accuracy still defines every Longines calibre produced today.

Historical milestones

  1. 1832

    Auguste Agassiz founds Longines in Switzerland.

  2. 1872

    Longines earns its first international recognition for precision timekeeping.

  3. 1969

    The quartz era forces Longines to redefine mechanical watchmaking.

  4. 1990

    Longines enters the modern collector market with its signature lines.

  5. 2024

    Longines continues to produce Master Collection, HydroConquest, Spirit and other icons in limited numbers.

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