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Universal Genève 215

Probable

One of the earliest micro-rotor automatics and, at 4.1mm, the thinnest automatic movement in the world when it appeared. It replaced the bumper 138SS in the Polerouter in spring 1955, at the same moment the dial spelling changed from Polarouter to Polerouter — which is what makes the caliber and the dial mutually checkable. A 57-hour reserve in 1955, from a movement this thin, was exceptional and remains respectable.

Specifications

Movement manufacturer
Universal Genève
Production
1955–?
Power reserve
57 hours
Height
4.1 mm
Winding
automatic

Architecture

Micro-rotor automatic: the winding weight is recessed into the movement plate rather than mounted above the bridges, so the automatic mechanism adds almost nothing to the movement's height. 4.1mm tall.

Authentication notes

  • MovementProbable

    A micro-rotor is unmistakable once the caseback is off

    The movement looks like a manual-wind caliber with a small weight let into the plate, not like a conventional automatic with a rotor sweeping over the bridges. A Polerouter opened to reveal a full overhead rotor is not carrying a Universal micro-rotor — most often because the original was replaced during a repair rather than because the watch is counterfeit.

Service practice

Thin movements have thin parts and small tolerances, parts are long out of production, and few watchmakers take them on. A non-running example is common and a serviced one has frequently had components replaced from donors — neither is a finding against the watch.

Related calibers

References using this caliber

Provenance of this record

Sources & Evidence

Secondary sourceSpecialist publication

Specialist horological writing on Universal Genève, the Polerouter and the micro-rotor

Established horological publications and dealer research

Accessed
2026-08-19

Cited for

This referenceProbable
Secondary sourceAuction archive

Auction-house archives and condition reports for Universal Genève

Phillips, Sotheby's, Christie's, Bonhams and specialist houses

Accessed
2026-08-19

Cited for

This referenceProbable

Last verified: Not yet reviewed