Does Longines make its own movements?

No — all current Longines movements are ETA-based. The L888 family is manufactured by ETA exclusively for Longines (ETA A31.L11) and is not available to other brands.

What was the Calibre 13ZN?

The first flyback chronograph wristwatch movement produced commercially — introduced in 1936 and produced until the early 1970s. It used a column wheel and the flyback function Longines had developed in 1934.

Which Longines movements are COSC-certified?

The L888.4 (Record, Spirit, Spirit Zulu Time), L791.4 (Spirit Flyback), and L844.4 (Spirit Zulu Time). The Record (2017) was the first Longines collection to carry COSC as a universal production standard.

What is the silicon balance spring?

A balance spring made from silicon rather than traditional metal alloy. Silicon is non-magnetic, corrosion-resistant, and maintains consistent elasticity across temperature variation — improving accuracy and longevity.

Longines Calibres and Timing Heritage

Longines' movement history begins with the factory itself: when Ernest Francillon completed the first purpose-built watch factory at Les Longines in 1867, the first movement produced within it — the Calibre 20A — established a production lineage that has continued without interruption for over 155 years. The milestones in that history are not incidental: the 1878 Calibre 20H was one of the first chronograph movements to win a gold medal at a world exposition; the 1913 Calibre 13.33Z was the first chronograph movement designed for a wristwatch; the 1936 Calibre 13ZN was the first flyback chronograph wristwatch movement produced commercially. These are primary documents in the history of mechanical timekeeping. The current production calibres — all ETA-based — are modern instruments with silicon springs and precision certification; understanding what they evolved from provides context for what they represent.

The Calibre 20H was Longines' first chronograph movement — a pocket watch calibre that won the gold medal at the 1878 Paris Exposition Universelle . The 20H was a mono-pusher chronograph: a single push engaged and stopped the chronograph function; a second push reset it. This was the standard chronograph architecture of the period. The gold medal at Paris was significant: the exposition was the most prominent scientific and industrial competition of its era, and the Longines precision record that the brand later used as its identity began with this award.

The Calibre 13.33Z of 1913 was the first chronograph movement designed specifically for a wristwatch . The move from pocket watch to wristwatch was not merely a change of case shape: it required a movement small enough to fit a wristwatch case while maintaining the structural integrity required by the chronograph mechanism. The 13.33Z solved this problem. It established Longines as the pioneer of wristwatch chronograph technology at a moment when the wristwatch form was itself still evolving from novelty to mainstream instrument.

The flyback function — activated by a single push that simultaneously stops, resets, and restarts the chronograph — was developed by Longines in 1934 and commercialised in the 13ZN two years later. The function was designed for pilots and navigators who needed to time sequential intervals without the three-step stop–reset–start sequence of a conventional chronograph. The 13ZN remained in production until the early 1970s — an extraordinary run of nearly four decades for a single architecture.

Calibre	Base	Beat Rate	Power Reserve	Silicon Spring	COSC	Used In
L888.4	ETA A31.L11	25,200 vph	64 hours	Yes	Yes	Record, Spirit, Spirit Zulu
L888.5	ETA A31.L11	25,200 vph	59 hours	Yes	No	HydroConquest
L888.6	ETA A31.L11	25,200 vph	72 hours	Yes	No	Conquest
L688	ETA-based	25,200 vph	54 hours	No	No	Conquest chrono, Avigation Big Eye
L791.4	ETA 7753 (modified)	28,800 vph	68 hours	Yes	Yes	Spirit Flyback
L844.4	ETA-based GMT	25,200 vph	—	Yes	Yes	Spirit Zulu Time
L899	ETA-based	25,200 vph	64 hours	Yes	No	Master Collection moonphase
L897	ETA-based	25,200 vph	64 hours	No	No	Master Collection annual calendar
L678	ETA Valjoux 7751	28,800 vph	—	No	No	Master Collection chrono-moonphase
L592	ETA A20.L01	—	40 hours	No	No	DolceVita automatic

The L791.4 is a modified ETA 7753 — itself derived from the ETA 7750 architecture — with a column wheel controlling the chronograph mechanism rather than a cam-and-lever system. The column wheel provides more consistent engagement and release across the chronograph's operating life, and is associated with higher-quality chronograph construction. The L791.4 runs at 28,800 vph (faster than the L888 family) and carries COSC certification . It is used exclusively in the Spirit Flyback.