Wear a smartwatch with your Seiko Prospex SPB143

Wear a smartwatch with your Seiko Prospex SPB143

Smartlet is compatible with the Seiko Prospex SPB143. Lug width: 20mm / 21mm / 22mm - natively supported with no adapter. Installation uses the standard spring-bar system. No modification to the watch required. Fully reversible in seconds.
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Seiko Prospex SPB143 compatibility

Wear a smartwatch with your Seiko Prospex SPB143

In short Smartlet is compatible with the Seiko Prospex SPB143. Lug width: 20mm / 21mm / 22mm - natively supported with no adapter. Installation uses the standard spring-bar system. No modification to the watch required. Fully reversible in seconds.

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.

Wear yours How it works
The problem
Choosing between health data and horological heritage every morning.
The solution
Smartlet One replaces your Seiko Prospex SPB143's strap via the standard spring-bar system and positions your smartwatch on the same wrist. Both watches run simultaneously, with no modification to the watch and full reversibility in seconds.
Model
Seiko Prospex SPB143
Lug width
20mm / 21mm / 22mm
References
17covered
Reversible
In seconds

Choose your edition

One mechanism. Three personalities.

Every Smartlet One includes the dedicated adapter for your wearable. Pick the finish that matches your style.

Smartlet One - Shadow - Smartlet

For the explorer

Smartlet One - Shadow

€399,00

4.9 (14)

Stealth. Switch in seconds, leave no trace.

  • Material SS316L steel, black PVD
  • Weight ~100g
  • Compatible with Rolex, Omega, Seiko + 100 more
Buy now
Compatibility

Seiko Prospex SPB143 models supported

Covered references

17 references covered.

ReferenceMaterialDialLugSmartlet
SRP777Stainless Steel 42mmBlack22mmCompatible
SRP773Stainless Steel 42mmBlue22mmCompatible
SRPB51Stainless Steel 42mmGrey22mmCompatible
SRPB49Stainless Steel 42mmBlue22mmCompatible
SPB101Stainless Steel 42mmBlack20mmCompatible
SPB103Stainless Steel 42mmBlue20mmCompatible
SPB143Stainless Steel 42mmGrey20mmCompatible
SPB147Stainless Steel 42mmBrown20mmCompatible
SPB151Stainless Steel 42mmBlack20mmCompatible
SPB153Stainless Steel 42mmGreen20mmCompatible
SBDB025Titanium 42mmBlue22mmCompatible
SBDB021Titanium 42mmBlack22mmCompatible
SRPA21Stainless Steel 42mmBlue/Red22mmCompatible
SNE435Stainless Steel 42mmBlue20mmCompatible
SSC009Stainless Steel 42mmBlack21mmCompatible
SRPC93Stainless Steel 42mmBlue Gradient22mmCompatible
SRPC91Stainless Steel 42mmBlue Gradient22mmCompatible

Seiko Prospex SPB143 lug widths: 20mm / 21mm / 22mm

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.
Frequently paired

Smartwatches worn with Seiko Prospex SPB143

The most common combinations our customers wear. Find your mechanical watch and discover the right Smartlet edition.

Apple Watch
Series 0 to Ultra 3
Whoop
5.0 / MG
Garmin Forerunner
255 to 965
Samsung Galaxy Watch
Series 4 to 7
Withings ScanWatch
Light / 2 / Nova
View all brands
27 brands covered
Also compatible

Other brands

Other iconic models in the Smartlet compatibility library.

Submariner
Daytona
GMT-Master
Datejust
Yacht-Master
Sky-Dweller
Explorer
Seamaster 300m
Speedmaster
Planet Ocean
Constellation
De Ville
Monaco
Carrera
Formula 1
Aquaracer
Portugieser
Navitimer
Superocean
Avenger
Black Bay
Pelagos
Ranger
Luminor
Radiomir
Submersible
SKX
Presage
Khaki Field
BR 03-92
Fifty Fathoms
Reverso
SUB 300
Spring Drive
Essence Leggera
Aquis
Divers Sixty-Five
Chronograph 1
Captain Cook
Superman Heritage
El Primero
Monarch
Black Bay 58 GMT
View all models
Watch brand compatibility guide

Step by step

Replace your strap
01

Replace your strap

Smartlet replaces your mechanical watch strap via the standard spring-bar system. Classic, Shadow, or Titanium. No tools required.

Connect your wearable
02

Connect your wearable

Smartlet uses a dedicated adapter or native lug pins depending on your smartwatch. The connector snaps onto the Smartlet module. Zero modification to the mechanical watch.

Wear both simultaneously
03

Wear both simultaneously

Both watches sit on the same wrist. All smartwatch sensors maintain direct skin contact and operate normally.

Questions

Frequently asked questions

  • 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. Smartlet replaces the standard strap via the spring-bar system. No modification to the watch is required. The setup is fully reversible.
  • Will Smartlet scratch or damage my Seiko Prospex SPB143?
    No. Smartlet replaces the strap only and makes no contact with the Seiko Prospex SPB143 case or crystal. All contact points are non-abrasive. The system is fully reversible and leaves no trace on the watch.
  • Which smartwatches can I wear with my Seiko Prospex SPB143?
    Smartlet is compatible with Apple Watch, Samsung Galaxy Watch, Garmin Fenix, 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.
  • Where can I buy Smartlet for the Seiko Prospex SPB143?
    Smartlet is available at smartlet.io in Classic, Shadow, and Titanium finishes. Compatible with the Seiko Prospex SPB143 and its 20mm / 21mm / 22mm lug width. No additional accessory required for standard lug widths between 18mm and 24mm.
  • Does Smartlet damage or modify my mechanical watch?
    No. Smartlet replaces your standard watch strap using the existing spring-bar system. It makes no permanent modification to the watch case, lugs, or dial. The process is fully reversible in seconds. Your mechanical watch is unaffected and can be worn independently at any time by reinstalling its original strap. Smartlet is engineered to watchmaker tolerances and tested with the same care that goes into the watches it pairs with.