Wear a smartwatch with your Cartier Santos de Cartier Large

Wear a smartwatch with your Cartier Santos de Cartier Large

Smartlet is compatible with the Cartier Santos de Cartier Large. Lug width: 19mm / 20mm / 23mm / 24mm - 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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Cartier Santos de Cartier Large compatibility

Wear a smartwatch with your Cartier Santos de Cartier Large

In short Smartlet is compatible with the Cartier Santos de Cartier Large. Lug width: 19mm / 20mm / 23mm / 24mm - natively supported with no adapter. Installation uses the standard spring-bar system. No modification to the watch required. Fully reversible in seconds.

The Santos was the first wristwatch designed by Louis Cartier for Alberto Santos-Dumont in 1904, who needed to check his watch while flying. The exposed screws, the square case, the integrated bracelet all functional, all now iconic. History and technology on one wrist.

Wear yours How it works
The problem
Choosing between health data and horological heritage every morning.
The solution
Smartlet One replaces your Cartier Santos de Cartier Large'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
Cartier Santos de Cartier Large
Lug width
19mm / 20mm / 23mm / 24mm
References
13covered
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 (17)

Stealth. Switch in seconds, leave no trace.

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

Cartier Santos de Cartier Large models supported

Covered references

13 references covered.

ReferenceMaterialDialLugSmartlet
W20106X8Stainless Steel 39.8mmWhite20mmCompatible
W20072X7Steel/Yellow Gold 39.8mmWhite23mmPre-order
W20073X8Stainless Steel 39.8mmWhite23mmPre-order
W20091X7Stainless Steel 39.8mmWhite24mmCompatible
WSSA0006steel / ADLC coating 39.8mmBlack23mmPre-order
WSSA0014steel / ADLC coating 39.8mmBlack23mmPre-order
WJSA001818K Pink Gold 35.1mmSilver19mmCompatible
WSSA0022Stainless Steel 35.1mmSilver19mmCompatible
W2SA0011Steel/Yellow Gold 35.1mmSilver19mmCompatible
WGSA005218K Pink Gold 39.8mmBurgundy Lacquer20mmCompatible
SDSM-MR-2023Titanium/Sapphire 39.8mmSkeleton20mmCompatible
SD-TOKYO-2019Steel 39.8mmNavy Tokyo20mmCompatible
WGSA003218K Pink Gold 39.8mmSilver20mmCompatible

Cartier Santos de Cartier Large lug widths: 19mm / 20mm / 23mm / 24mm

The Santos was the first wristwatch designed by Louis Cartier for Alberto Santos-Dumont in 1904, who needed to check his watch while flying. The exposed screws, the square case, the integrated bracelet all functional, all now iconic. History and technology on one wrist.
Frequently paired

Smartwatches worn with Cartier Santos de Cartier Large

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
Prospex
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 Cartier Santos de Cartier Large?
    Yes. The Cartier Santos de Cartier Large uses a 19mm / 20mm / 23mm / 24mm 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 Cartier Santos de Cartier Large?
    No. Smartlet replaces the strap only and makes no contact with the Cartier Santos de Cartier Large 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 Cartier Santos de Cartier Large?
    Smartlet is compatible with Apple Watch, Samsung Galaxy Watch, Garmin Forerunner, Garmin Venu, Google Pixel Watch, Polar Vantage, Fitbit Charge, Huawei Watch GT, Withings ScanWatch, Coros, Suunto, and Whoop. The Cartier Santos de Cartier Large with its 19mm / 20mm / 23mm / 24mm lug width is compatible with the full Smartlet range.
  • Where can I buy Smartlet for the Cartier Santos de Cartier Large?
    Smartlet is available at smartlet.io in Classic, Shadow, and Titanium finishes. Compatible with the Cartier Santos de Cartier Large and its 19mm / 20mm / 23mm / 24mm 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.