The Milgauss model with reference 6541 with black revolving bezel was introduced into the market in the 1950s. It was designed for use in areas of high electro-magnetic radiation, such as research labs or power stations. The influence of radiation on the balance work results in losing accuracy. These effects can be reduced by using the principles of a "Faraday Cage", e.g. by placing the movement in an iron inner case shielding the movement.
The Faraday Cage is attributed to the physicist Michael Faraday who, in 1863, built a room coated with metal foil and allowed high-voltage discharges from an electrostatic generator to strike its outside. He then used an electroscope to show that there was no excess electric charge on the inside of the room's walls.
The present watch features in addition the very rare and sought after honeycomb dial, consisting of two cross aluminum layers to protect it even further against magnetic radiation.
In the mid 1960s, the redesigned reference 1019 with blank bezel was launched. For Milgauss models with this reference see lots 18 and 116 in this sale.