Seikonaut 40mm Case – Gold
- In stock, ready to ship
Complete Your Build
The Yellow Gold Seikonaut delivers the boldest warm-tone finish in the lineup with a full gold PVD coating over 316L stainless steel. At 9.95 mm with a solid caseback, this 40 mm case keeps the ultra-thin Nautilus silhouette while making a deliberate visual statement. The brushed and polished gold surfaces catch light from every angle, and the sapphire crystal is available with clear or blue AR coating. With a screw-down crown rated to 50 m water resistance and compatibility with all NH-family movements and 30.8 mm dials, this case is for builders who want their Nautilus mod to command attention.
Specifications
| Specification | Value |
|---|---|
| Diameter | 40 mm (10H–4H) × 38 mm (12H–6H) |
| Thickness | 9.95 mm (solid caseback) / 10.3 mm (exhibition caseback) |
| Material | 316L Stainless Steel with gold PVD |
| Finish | Brushed and polished gold |
| Crystal | Sapphire (clear or blue AR coating) |
| Water Resistance | 50 m |
| Dial Fit | 30.8 mm |
| Crown | Screw-down, included |
Compatibility
Movements: NH35, NH36, NH38, NH70, NH71, NH72 — all standard Seiko NH-family automatics fit without modification. The crown stem must be cut to length during installation.
Dials: 30.8 mm dials only. Gold and champagne dials create a monochromatic luxury look. Black, dark green, and navy dials provide striking contrast against the gold case. White dials give a clean, classic two-tone feel.
Bracelet: Gold Seikonaut integrated bracelet included with the case. Standard spring bar attachment at the lugs, so you can swap to a rubber strap if you prefer — black and dark green rubber straps pair well with the gold case.
Not compatible: 7S26 and 7S36 movements use a different stem height and are not recommended for this case.
What’s Included
- Gold Seikonaut integrated bracelet (included)
- Seikonaut case body (316L steel, gold PVD coating)
- Caseback (solid or exhibition, depending on variant selected)
- Screw-down crown
- Crystal gasket and caseback gasket
- Sapphire crystal (pre-installed, clear or blue AR coating)
Movement, dial, hands, strap, and tools are not included. You will need a case opener, hand press, stem cutter, movement holder, and rodico to complete your build.
Why We Chose This Case
A full gold Nautilus is one of the most iconic references in watchmaking, and builders have been asking for a gold Seikonaut since the silver version launched. The challenge with gold PVD cases in the mod market is that most look cheap — the tone is too yellow, the finish is too uniform, or the case is too thick to carry the gold aesthetic convincingly. The Seikonaut gold addresses all three issues: the PVD shade is tuned to a warm but restrained yellow gold, the brushed-and-polished finishing adds the surface variety that genuine gold watches have, and the 9.95 mm thickness avoids the chunky look that undermines most gold mod cases. The result reads like a gold sports watch, not a gold-painted mod.
Frequently Asked Questions
Is the gold case real gold?
No. The case is 316L stainless steel with a PVD gold coating. PVD (Physical Vapor Deposition) is more durable and scratch-resistant than traditional gold plating. The look is gold-tone, not solid gold, which keeps the price accessible while delivering the visual impact of a full gold watch. The PVD shade is tuned to a warm, restrained yellow gold rather than the overly bright tone found on cheaper alternatives.
Does the gold PVD match the NH72 movement bridges?
Yes, closely. The NH72 skeleton movement has golden-toned bridges, and the Seikonaut gold PVD shade was selected to complement that tone. Pairing this case with the NH72 and an exhibition caseback creates a unified gold build from case to movement bridges.
Does the case ship with a bracelet?
Yes. The gold Seikonaut integrated bracelet ships with the case and creates the full luxury look out of the box. For a sportier feel you can swap to a black rubber strap — maximum contrast, lets the gold case take center stage. Green and navy rubber straps also pair well for a bold color-on-gold combination.
How thin is this compared to other gold Nautilus mod cases?
At 9.95 mm with a solid caseback, the Gold Seikonaut is one of the thinnest gold Nautilus-style cases available. Most competitors measure 12–14 mm. A thinner gold case reads more like a genuine gold sports watch and less like a plated mod, which is critical for the gold finish to look convincing on the wrist.
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