Seiko Nautilus Open Heart Automatic 40mm
Seiko Nautilus Open Heart Automatic 40mm
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Shipping, Delivery & Exchanges
Shipping, Delivery & Exchanges
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DESCRIPTION
Watches — watch
Seiko Nautilus Open Heart Automatic 40mm
A steel case at 40 mm on a leather strap, with sapphire crystal keeping the face as clear as the first morning.

40 mm Steel Case
A steel case at 40 mm lands between discreet and present, which is where most wrists want it.
Leather Strap
Leather takes the shape of your own wrist in a few wearings and then stays there.
Sapphire crystal
Sapphire crystal is why the face still looks new when the rest of the watch has a history.
What steel and leather do together
Steel gives the case its weight and its edges; leather gives the wrist something that softens into the shape of it. Between them, sapphire crystal is the part that has to stay clear, and it does. At 40 mm the case is substantial without pushing a cuff out of shape.


The impression steel and leather leave
A watch like this is read rather than discussed. Someone takes it in across a table, while you are reaching for something or turning your hand over, and they file you slightly differently. The second look is the part worth having.
Past what is printed
Leather warming to the wrist
Leather is the one part of a watch that changes to fit you rather than the other way round. After a few wearings the strap has your wrist in it and nothing else will sit quite the same.
You will find yourself fastening it slowly, which is not something anyone plans. That is the half of owning a watch that no specification covers.
What you are getting
- Case size
- 40 mm
- Strap
- Leather Strap
- Crystal
- Sapphire crystal
- Colours
- Black, Orange, Green
Colourways
One case, three different tempers
The case and the crystal stay put; what changes is the tone, and the tone decides which half of your wardrobe the watch belongs to. Pick on that basis and it will be the one you actually reach for.



Why it costs what it costs
We hold this stock ourselves and send it out from our own shelves. No boutique floor to pay for, nobody taking a cut in between — one step from our rack to your door instead of four. The piece is not cheaper; the route is shorter.
Store offer
Two pieces get you a cap. Three get you a cap and a wallet.
It runs across the whole store, so the pieces do not have to match.
- Any two items — a cap goes in the box, free.
- Any three or more — the cap plus a wallet.
On short series generally
These go out in small numbers and the three do not move at the same pace — a restock is not guaranteed, and the next lot will not match.
Pick yours above.

Italian Heritage Since 1975
Founded in Italy in 1975, Arkon began as a family business driven by a passion for timeless men’s fashion and refined craftsmanship. What started as a small Italian house has grown into a recognized name in contemporary luxury, bringing together tradition, sophistication, and modern design.
Today, Arkon carries its heritage forward, creating a vision of menswear for those who believe true style is timeless.