The Rolex Oyster Perpetual Milgauss is a wristwatch model introduced by Rolex in 1956 (model number 654). The Milgauss was designed to meet the demands of the scientific community working around electromagnetic fields. The first of its kind, it is capable of withstanding magnetic fields of up to 1,000 gauss and became known for being worn by scientists at the European Organization for Nuclear Research (CERN) in Geneva. Its resistance to magnetic interference is provided by a shield, inside the case, made of ferromagnetic alloys, which protects the movement. This shield consists of two components, one screwed to the movement and the other to the case. In addition, its Caliber 3131 movement contains paramagnetic materials.

The name Milgauss is derived from the French ‘mille’, meaning one-thousand, and ‘gauss’, the unit of a magnetic field.

The original Milgauss was very similar in appearance to the Rolex Submariner, with an oversized case and bezel, with a Twinlock crown, and a riveted Oyster bracelet. Although the Milgauss went through only two different models (6541, 1019) it had  numerous configuration changes before being discontinued in 1988. In the 1960s, Rolex launched the Milgauss 1019. However, this particular model looks so different from its predecessors that at first glance the Milgauss link is not immediately clear.

The Milgauss remains a sought-after model amongst Rolex collectors due to its relatively low sales and popularity during the 1960s and 1970s, it has become rare in today's vintage watch market. A vintage Milgauss signed by Tiffany & Co. recently sold for over $32,000.