Longines has a long history of producing precision timekeepers for professional and specialist applications beyond the conventional wristwatch. Deck and instrument watches provided an accurate, easily readable mechanical time source that could be securely mounted where required. The unusual Reference 6624 belongs firmly within this tradition, combining a highly legible instrument-style dial with Longines' hand-wound Calibre 12.68ZS and a purpose-built blackened case designed for fixed mounting rather than wrist wear.

What's on Offer

We are delighted to offer this particularly unusual Longines Reference 6624 mechanical deck watch, dating from 5th July 1954 and accompanied by its Longines Extract from the Archives.

Although its dial and proportions initially give the appearance of a wristwatch, the construction of the case reveals its true purpose. Rather than conventional strap lugs, the blackened steel case incorporates substantial rectangular extensions at 12 and 6 o'clock, each pierced with a large circular mounting hole. These allow the watch to be secured into a suitable holder, panel or fixture, making this a purpose-built instrument rather than a conventional wristwatch.

The black dial has been designed with legibility firmly in mind. Large white Arabic numerals are surrounded by a clear outer minute track, with alternating circular and rectangular markers providing additional reference points around the dial. Slender hands and a central sweep seconds hand complete the wonderfully stark and functional arrangement, while the restrained LONGINES signature is positioned beneath 12 o'clock.

Powering the watch is the Longines Calibre 12.68ZS, a 17-jewel manually wound mechanical movement with an approximate power reserve of 41 hours. The movement carries serial number 9087499.

Its appearance is undeniably reminiscent of military and naval instrumentation of the period, and deck watches were used in a variety of professional maritime and military environments. However, there are no visible military issue markings on this example and, accordingly, we make no claim that this particular watch was military issued.

What makes the Reference 6624 especially fascinating today is its unusual configuration. It occupies the territory between watch and instrument: compact enough to resemble a wristwatch, yet clearly constructed to be mounted rather than worn. Very few vintage Longines pieces encountered today have quite the same utilitarian character.

The blackened case displays honest signs of age and use, including areas of wear to the finish that reveal the metal beneath, together with some surface marking and ageing around the mounting points. These characteristics suit the industrial nature of the piece beautifully. The black dial remains remarkably clean and highly legible, retaining excellent contrast between its white markings and dark background.

Accompanied by its Longines Extract from the Archives, this is an intriguing and seldom-seen example of the manufacturer's specialist instrument watchmaking from the 1950s.