A replica Rolex Milgauss 116400 is a third-party copy of Rolex's anti-magnetic 40 mm Oystersteel model, built to match the look of the original reference: the smooth polished bezel, the black or white dial, and the orange lightning-bolt seconds hand. A replica copies the appearance and the case proportions. It does not contain a Rolex movement, it is not made or serviced by Rolex, and it is not a genuine watch.

What the Milgauss 116400 actually is

Rolex introduced the Milgauss 116400 in 2007 as a modern version of a 1950s design made for engineers and scientists who worked near magnetic fields. The reference measures 40 mm across, sits on a steel Oyster bracelet, and is rated to resist magnetic fields up to 1,000 gauss, which is where the name comes from. The dial carries no date. That keeps the layout symmetrical and makes the model easier to judge as a replica, because there is no date wheel to align and no magnifying lens to get right. The 116400GV is the variant with the green-tinted sapphire crystal.

Key specs to compare

• Case: 40 mm Oystersteel, smooth polished bezel
• Movement: Rolex caliber 3131 in the genuine watch, with a paramagnetic escapement
• Magnetic resistance: 1,000 gauss, the headline feature of the line
• Dial: black or white, applied hour markers, orange lightning-bolt seconds hand
• Crystal: sapphire, green-tinted on the GV version
• Water resistance: 100 m on the original
• Bracelet: Oyster with polished center links and a folding clasp

Treat that list as a checklist. Case diameter and thickness are the easiest values to measure with calipers, and they are also the ones budget copies get wrong most often.

Replica tiers and what changes between them

Replica Milgauss watches cluster into three broad groups, and the differences show up in materials, movement, and finishing rather than in the overall silhouette.

• Entry level: quartz or basic automatic movement, mineral glass, a lighter case, and dial printing that softens or smears under a loupe.
• Mid tier: automatic clone movement, sapphire crystal, 316L steel, correct 40 mm sizing, and reasonable brushing on the case and bracelet.
• Top tier: 904L steel, sapphire with anti-reflective coating, a 3131-style cloned movement, sharper dial text, and a seconds hand with the correct shape and color.

One feature no replica reproduces is the real magnetic protection. The genuine 3131 movement uses a paramagnetic escapement and specific alloys, so a copy fitted with a standard automatic movement will not hold up to 1,000 gauss in practice, even when the caseback is engraved with the number.

What to check before you buy

• Case size: confirm 40 mm across and roughly 13 mm thick, measured rather than quoted.
• Lug width: 20 mm, so the bracelet and any replacement strap sit flush.
• Dial and hands: look for even lume plots, clean text, and a lightning-bolt seconds hand with a sharp edge.
• Crystal: sapphire should be clear at an angle, with no distortion over the dial. The GV version needs a green tint, not a green film.
• Bracelet: check the clasp action, the polish on the center links, and whether the end links sit tight against the case.
• Water resistance: do not assume it. A gasket and a claim are not the same thing, and most sellers offer no pressure rating you can verify.

Legal and practical notes

Replica watches carry the Rolex name and logo without permission, which makes them counterfeit goods in most markets, including the United States. Buying, selling, or shipping them can carry legal consequences, and resale value is effectively zero. There is also no manufacturer warranty and no authorized service network, so any repair falls to a local watchmaker. If the anti-magnetic function matters to your work, only the genuine reference delivers it.

Quick recap

The Milgauss 116400 is a 40 mm, date-free, anti-magnetic Rolex that was retired along with the rest of the line in 2023. A good replica gets the proportions, dial layout, and bracelet finish close to the original. It will never match the movement, the 1,000 gauss rating, or the legal status of the real thing, and those are the three points worth weighing before you spend anything.