Rolex Milgauss 40 Oystersteel — Blue Dial Green Crystal | Ref. 116400GV

The Milgauss occupies a unique and largely uncontested position in Rolex's catalogue: a purpose-engineered antimagnetic sports watch conceived in the 1950s for physicists and engineers working in high-flux laboratory environments. Reference 116400GV — the 'GV' suffix denoting verre vert, or green glass — reintroduced the Milgauss in 2007 with the addition of a proprietary green sapphire crystal, tinted to a deep emerald tone through a complex colouration process applied during manufacture. This element alone distinguishes the Milgauss from every other production wristwatch.

The blue dial of the 116400GV presents a graduated electric-blue lacquered surface with applied Oystersteel index hour markers and the model's characteristic lightning-bolt seconds hand — an homage to the original 1956 reference 6541 and its association with electrical engineering. The Oystersteel case, measuring 40 mm with a domed stainless steel bezel and screw-down Twinlock crown, provides waterproofness to 100 metres. The Oyster bracelet in heavy Oystersteel with a folding Oysterclasp delivers a robust, utilitarian wearing experience appropriate to the watch's professional heritage.

The movement, calibre 3131, is a variant of the 3130 base calibre constructed with an internal antimagnetic shield — a soft-iron Faraday cage surrounding the escapement and balance wheel assembly that deflects magnetic fields in excess of 1,000 gauss. This passive shielding approach, refined across successive generations, renders the movement immune to the magnetic environments that afflict conventional mechanical watches. With a Parachrom hairspring, Paraflex shock absorbers, and Superlative Chronometer certification, the 3131 is among the most technically specific movements in the Rolex catalogue.