A century of leadership

In 1914, the Kew Observatory near London granted a "Class A" certificate to a wristwatch for the very first time. This major achievement by a small Rolex watch astonished the world and marked the advent of the modern precision wristwatch.

Until then, such a certification, which attested to the highest chronometric precision, had generally been awarded only to large marine chronometers. This first chronometer wristwatch met observatory's demanding criteria: 45 days of tests, in five different positions and at three different temperatures. The brand perfected the concept of the modern  watch in 1926 by inventing a waterproof Oyster case and then, in 1931, by developing the self-winding Perpetual rotor movement.