Rolex 1066

Last updated: July 26, 2025

Brand

Caliber Number

1066

Production Period

1955-1959

Lignes

12.5′′′

Diameter

28.5 mm

Height

6.5 mm

Power Reserve

Unconfirmed

Frequency

18,000 A/h (2.5 Hz)

Jewels

25

Escapement

Swiss Lever

Anti-Shock Device

Kif-Flector

Hand Count

4

Manufacture Region

Unconfirmed

Functions

Hours, Minutes, Central Seconds, Date, GMT (24-hour hand slaved to hour hand)

Rolex 1066 Description

The Rolex Caliber 1066 is the celebrated movement that powered the original Rolex GMT-Master, reference 6542, starting in 1955. Developed for Pan American Airways pilots at the dawn of the jet age, this caliber was a technical achievement of its time. Based on the chronometer-grade Caliber 1030 architecture, the 1066 added a date function and a signature 24-hour hand complication. This fourth hand was geared to the main hour hand and completed a single rotation every 24 hours, pointing to a corresponding 24-hour scale on a rotating bezel. This system allowed pilots to track a second time zone (such as GMT) in addition to their local time. Like other 10xx series movements, it featured Rolex’s efficient bi-directional automatic winding system and a Breguet overcoil hairspring for stability. The 1066 was produced for a short period, eventually being replaced by the 15xx series around 1959, but its role in launching one of the world’s most iconic travel watches gives it a significant place in horological history.

Watches Using The Rolex 1066 Caliber

A stainless steel Rolex GMT-Master wristwatch with a red and blue bezel, black dial, and metal bracelet, inspired by the iconic 6542 model.
A vintage Rolex Oyster Perpetual wristwatch inspired by the iconic Rolex Milgauss 6541, featuring a black dial, silver band, and luminous hour markers.