Wear a smartwatch with your Seiko Prospex | Smartlet
Wear a smartwatch
with your Seiko Prospex SPB143
The SPB143 is a modern reinterpretation of Seiko's 1965 diver the first Japanese dive watch. The dark blue dial, the fully brushed case, and the 6R35 movement with 70-hour reserve represent extraordinary value.
Covered references
| Reference | Smartlet | Lug width | Case | Case material | Dial |
|---|---|---|---|---|---|
| SRP777 | Compatible | 22mm | - | Stainless Steel | Black |
| SRP773 | Compatible | 22mm | - | Stainless Steel | Blue |
| SRPB51 | Compatible | 22mm | - | Stainless Steel | Grey |
| SRPB49 | Compatible | 22mm | - | Stainless Steel | Blue |
| SPB101 | Compatible | 20mm | - | Stainless Steel | Black |
| SPB103 | Compatible | 20mm | - | Stainless Steel | Blue |
| SPB143 | Compatible | 20mm | - | Stainless Steel | Grey |
| SPB147 | Compatible | 20mm | - | Stainless Steel | Brown |
| SPB151 | Compatible | 20mm | - | Stainless Steel | Black |
| SPB153 | Compatible | 20mm | - | Stainless Steel | Green |
| SBDB025 | Compatible | 22mm | - | Titan | Blue |
| SBDB021 | Compatible | 22mm | - | Titan | Black |
| SRPA21 | Compatible | 22mm | - | Stainless Steel | Blue/Red |
| SNE435 | Compatible | 20mm | - | Stainless Steel | Blue |
| SSC009 | Compatible | 21 mm | - | Stainless Steel | Black |
| SRPC93 | Compatible | 22mm | - | Stainless Steel | Blue Gradient |
| SRPC91 | Compatible | 22mm | - | Stainless Steel | Blue Gradient |
The Seiko Prospex SPB143 uses a 20mm lug width. Smartlet One attaches to the same wrist via a spring-bar adapter. Zero contact with the watch case, lugs, or bracelet. Fully reversible in seconds.
Smartwatches to pair with your Seiko Prospex SPB143
All smartwatches below can be worn simultaneously with your Seiko Prospex SPB143 via Smartlet One.
Other Seiko models
All Seiko models below are also compatible with Smartlet One.
Similar models from other brands
Watch lovers who own a Seiko also pair Smartlet with these models.
Frequently asked
Does Smartlet work with the Seiko Prospex SPB143?
Yes. The Seiko Prospex SPB143 uses a 20mm / 21mm / 22mm lug width and is fully compatible with Smartlet One. Smartlet One replaces the standard strap via the spring-bar system and positions your smartwatch on the same wrist. The Seiko Prospex SPB143 requires no modification, no drilling, and no adhesive. The setup is fully reversible in seconds and your Seiko can be worn independently at any time by reinstalling its original strap.
Will Smartlet scratch or damage my Seiko Prospex SPB143?
No. Smartlet One makes no contact with the Seiko Prospex SPB143 case, bezel, or crystal. It replaces the strap only, using the existing spring-bar slots. The module is manufactured in 316L stainless steel or titanium with polished and brushed finishing, and all contact points are non-abrasive. Your Seiko Prospex SPB143 is protected throughout. The system is fully reversible and leaves no trace.
Which smartwatches can I wear with my Seiko Prospex SPB143?
Smartlet One is compatible with Apple Watch (all series), Samsung Galaxy Watch (4, 5, 6, 7), Garmin Fenix (6, 7, 8), Garmin Forerunner, Garmin Venu, Google Pixel Watch, Polar Vantage, Fitbit Charge, Huawei Watch GT, Withings ScanWatch, Coros, Suunto, and Whoop. The Seiko Prospex SPB143 with its 20mm / 21mm / 22mm lug width is compatible with the full Smartlet range. All smartwatch sensors remain operational when worn via Smartlet.
Where can I buy Smartlet One for the Seiko Prospex SPB143?
Smartlet One is available directly at smartlet.io in three finishes: Classic (316L stainless steel), Shadow (PVD black-coated 316L), and Titanium. All three finishes are compatible with the Seiko Prospex SPB143 and work with its 20mm / 21mm / 22mm lug width. Orders ship internationally from Europe. No additional accessory is required for standard lug widths between 18mm and 24mm.