AP x Swatch: Royal Pop conversion case
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Transform your Royal Pop into a full stainless-steel wristwatch. This conversion case rehouses your Swatch Sistem51 movement in a 39 mm, Royal Oak-inspired steel case with a sapphire crystal — the watch you already own keeps ticking, but on the wrist it reads as a proper integrated-sports watch instead of plastic.
What it is
The Royal Pop conversion case is an aftermarket stainless-steel case built to take a Swatch Sistem51 movement. You transplant your own Sistem51 into it, and the result is a slim 39 mm watch — octagonal integrated-sports bezel, sapphire crystal, 10 ATM water resistance — with a level of finishing the original plastic case can't come close to.
Specifications
| Case size | 39 mm |
| Lug-to-lug | 50 mm |
| Thickness | 9 mm |
| Crystal | Sapphire |
| Water resistance | 10 ATM (100 m) |
| Compatibility | Swatch Sistem51 only |
| Finishes | Silver, Gold, Rose Gold, Black PVD |
Frequently asked questions
Which watch does the Royal Pop conversion case fit?
It's built for the Swatch Sistem51 movement only. You move your Sistem51 out of its original case and into this one.
Does it come with a strap or bracelet?
The conversion case is sold on its own. It wears on a standard strap, so you can finish it with the Royal Pop strap, bracelet or band of your choice.
Is it water resistant?
Yes — rated 10 ATM (100 m) with the sapphire crystal and proper gaskets, so it handles rain and hand-washing. It is not a dive watch.
Which finishes are available?
Four: Silver, Gold, Rose Gold and Black PVD. Pick your finish at the top of the page.
Can you build it for me?
Want it built for you? See finished Royal Pop builds at Swatchmods.
Transform your Royal Pop into a full stainless-steel wristwatch. This conversion case rehouses your Swatch Sistem51 movement in a 39 mm, Royal Oak-inspired steel case with a sapphire crystal — the watch you already own keeps ticking, but on the wrist it reads as a proper integrated-sports watch instead of plastic.
What it is
The Royal Pop conversion case is an aftermarket stainless-steel case built to take a Swatch Sistem51 movement. You transplant your own Sistem51 into it, and the result is a slim 39 mm watch — octagonal integrated-sports bezel, sapphire crystal, 10 ATM water resistance — with a level of finishing the original plastic case can't come close to.
Specifications
| Case size | 39 mm |
| Lug-to-lug | 50 mm |
| Thickness | 9 mm |
| Crystal | Sapphire |
| Water resistance | 10 ATM (100 m) |
| Compatibility | Swatch Sistem51 only |
| Finishes | Silver, Gold, Rose Gold, Black PVD |
Frequently asked questions
Which watch does the Royal Pop conversion case fit?
It's built for the Swatch Sistem51 movement only. You move your Sistem51 out of its original case and into this one.
Does it come with a strap or bracelet?
The conversion case is sold on its own. It wears on a standard strap, so you can finish it with the Royal Pop strap, bracelet or band of your choice.
Is it water resistant?
Yes — rated 10 ATM (100 m) with the sapphire crystal and proper gaskets, so it handles rain and hand-washing. It is not a dive watch.
Which finishes are available?
Four: Silver, Gold, Rose Gold and Black PVD. Pick your finish at the top of the page.
Can you build it for me?
Want it built for you? See finished Royal Pop builds at Swatchmods.
Transform your Royal Pop into a full stainless-steel wristwatch. This conversion case rehouses your Swatch Sistem51 movement in a 39 mm, Royal Oak-inspired steel case with a sapphire crystal — the watch you already own keeps ticking, but on the wrist it reads as a proper integrated-sports watch instead of plastic.
What it is
The Royal Pop conversion case is an aftermarket stainless-steel case built to take a Swatch Sistem51 movement. You transplant your own Sistem51 into it, and the result is a slim 39 mm watch — octagonal integrated-sports bezel, sapphire crystal, 10 ATM water resistance — with a level of finishing the original plastic case can't come close to.
Specifications
| Case size | 39 mm |
| Lug-to-lug | 50 mm |
| Thickness | 9 mm |
| Crystal | Sapphire |
| Water resistance | 10 ATM (100 m) |
| Compatibility | Swatch Sistem51 only |
| Finishes | Silver, Gold, Rose Gold, Black PVD |
Frequently asked questions
Which watch does the Royal Pop conversion case fit?
It's built for the Swatch Sistem51 movement only. You move your Sistem51 out of its original case and into this one.
Does it come with a strap or bracelet?
The conversion case is sold on its own. It wears on a standard strap, so you can finish it with the Royal Pop strap, bracelet or band of your choice.
Is it water resistant?
Yes — rated 10 ATM (100 m) with the sapphire crystal and proper gaskets, so it handles rain and hand-washing. It is not a dive watch.
Which finishes are available?
Four: Silver, Gold, Rose Gold and Black PVD. Pick your finish at the top of the page.
Can you build it for me?
Want it built for you? See finished Royal Pop builds at Swatchmods.
Transform your Royal Pop into a full stainless-steel wristwatch. This conversion case rehouses your Swatch Sistem51 movement in a 39 mm, Royal Oak-inspired steel case with a sapphire crystal — the watch you already own keeps ticking, but on the wrist it reads as a proper integrated-sports watch instead of plastic.
What it is
The Royal Pop conversion case is an aftermarket stainless-steel case built to take a Swatch Sistem51 movement. You transplant your own Sistem51 into it, and the result is a slim 39 mm watch — octagonal integrated-sports bezel, sapphire crystal, 10 ATM water resistance — with a level of finishing the original plastic case can't come close to.
Specifications
| Case size | 39 mm |
| Lug-to-lug | 50 mm |
| Thickness | 9 mm |
| Crystal | Sapphire |
| Water resistance | 10 ATM (100 m) |
| Compatibility | Swatch Sistem51 only |
| Finishes | Silver, Gold, Rose Gold, Black PVD |
Frequently asked questions
Which watch does the Royal Pop conversion case fit?
It's built for the Swatch Sistem51 movement only. You move your Sistem51 out of its original case and into this one.
Does it come with a strap or bracelet?
The conversion case is sold on its own. It wears on a standard strap, so you can finish it with the Royal Pop strap, bracelet or band of your choice.
Is it water resistant?
Yes — rated 10 ATM (100 m) with the sapphire crystal and proper gaskets, so it handles rain and hand-washing. It is not a dive watch.
Which finishes are available?
Four: Silver, Gold, Rose Gold and Black PVD. Pick your finish at the top of the page.
Can you build it for me?
Want it built for you? See finished Royal Pop builds at Swatchmods.
Transform your Royal Pop into a full stainless-steel wristwatch. This conversion case rehouses your Swatch Sistem51 movement in a 39 mm, Royal Oak-inspired steel case with a sapphire crystal — the watch you already own keeps ticking, but on the wrist it reads as a proper integrated-sports watch instead of plastic.
What it is
The Royal Pop conversion case is an aftermarket stainless-steel case built to take a Swatch Sistem51 movement. You transplant your own Sistem51 into it, and the result is a slim 39 mm watch — octagonal integrated-sports bezel, sapphire crystal, 10 ATM water resistance — with a level of finishing the original plastic case can't come close to.
Specifications
| Case size | 39 mm |
| Lug-to-lug | 50 mm |
| Thickness | 9 mm |
| Crystal | Sapphire |
| Water resistance | 10 ATM (100 m) |
| Compatibility | Swatch Sistem51 only |
| Finishes | Silver, Gold, Rose Gold, Black PVD |
Frequently asked questions
Which watch does the Royal Pop conversion case fit?
It's built for the Swatch Sistem51 movement only. You move your Sistem51 out of its original case and into this one.
Does it come with a strap or bracelet?
The conversion case is sold on its own. It wears on a standard strap, so you can finish it with the Royal Pop strap, bracelet or band of your choice.
Is it water resistant?
Yes — rated 10 ATM (100 m) with the sapphire crystal and proper gaskets, so it handles rain and hand-washing. It is not a dive watch.
Which finishes are available?
Four: Silver, Gold, Rose Gold and Black PVD. Pick your finish at the top of the page.
Can you build it for me?
Want it built for you? See finished Royal Pop builds at Swatchmods.
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