ETA · Hand-wound, ultra-thin

7001 — the ultra-thin hand-wound calibre from Peseux

Peseux lineage

ETA/Peseux 7001 movement rebadged as the Longines L396.2, with the Longines name engraved on the bridge
Representative watch — photo: EMore98 / Wikimedia Commons, CC BY-SA 4.0
Photo of the movement
still to be verified
Calibre 7001
Type: hand-wound Jewels: 17 Frequency: 21,600 vph Height: 2.5 mm

In one line

The extra-flat hand-wound Peseux: 23.30 mm across, 2.50 mm tall, sub-seconds at six. ETA has stopped making it, and what is left on the market is old stock.

7001 against the D100: the handover

Stocks are running down and brands have spent years buying up what is left. In 2023 La Joux-Perret launched the D100: a 7001 to the same dimensions with a little more winding. Several brands have already made the switch without touching the case.

ETA/Peseux 7001La Joux-Perret D100
Diameter23.30 mm23.30 mm
Height2.50 mm2.50 mm
Frequency21,600 vph21,600 vph
Power reserve42 hours50 hours
In productionNoYes, since 2023
What you buy todayOld stockA new movement

The dimensions matching to a tenth of a millimetre is no accident: the D100 is built to drop into cases drawn around a 7001, with nothing redesigned. It also uses a different click and gives eight hours more power reserve.

On a second-hand watch it makes no difference which one you have. On a new watch sold as a '2.5 mm Swiss hand-wound movement', ask which of the two is inside.

Where it comes from

Peseux is a village in Neuchâtel and it was also an ébauche factory. Charles Berner founded it in 1923 and it specialised in one thing: flat calibres. It joined Ebauches SA in 1933 — the conglomerate that ETA would eventually emerge from — yet it went on signing movements with its own name for almost half a century, which was rare inside that group.

The 7001 arrived in 1971 and has not changed since. Ten and a half lignes, two and a half millimetres tall, sub-seconds at six. Peseux ceased to exist as a legal entity in 1979 and production moved to Fontainemelon, but the calibre carried on, now with ETA in front of the number. Somewhere north of two million are thought to have been made.

Its career was made by its height. An automatic needs a rotor on top and that costs millimetres; with a 2.50 mm hand-wound calibre you can build a dress watch under nine millimetres thick without inventing anything. Longines renamed it the L396.2, Omega used it in the hand-wound De Ville as the calibre 651, and Nomos built its entire first decade on it.

Three things almost nobody knows

Technical data

TypeHand-wound, extra-flat
OriginFabrique d'ébauches de Peseux (Neuchâtel)
Diameter23.30 mm (10½ lignes)
Height2.50 mm
Jewels17
Frequency21,600 vph (3 Hz)
Power reserve42 hours
SecondsSub-seconds at six
Shock protectionIncabloc
ProductionFrom 1971 · discontinued; successor: La Joux-Perret D100

What a watchmaker checks before buying one

A hand-wound movement two and a half millimetres deep forgives less than a thick one, and the winding is where you notice first. At the end of the wind the mainspring should stop dead. If the crown keeps turning against a soft resistance with no clear finish, either the winding pinion is chewed or the stem has been forced. Neither part can be ordered from a catalogue any more.

Next, the rate in the vertical positions. Thin mainplates distort under a knock or an over-tightened casing clamp screw, and a warped mainplate is invisible to the eye. What you see instead is a watch that keeps good time lying flat on the bedside table and poor time on the wrist.

Then the oil. No calibre turns up more often inside a watch that has spent twenty years in a drawer and 'runs perfectly'. It runs dry, which is a different thing. A 7001 that has not been serviced since the 1990s is grinding away its own pivots while it tells the time.

On spares, the right question is no longer whether the watchmaker knows the movement. It is whether they can get the parts. Ask about the balance and the mainspring in particular: those are the two that have become hard to find.

Watches that used it

Watch videos about this movement