Wear a smartwatch with your Cartier

Wear a smartwatch with your Cartier

Smartlet One is compatible with Cartier Santos, Tank, and Ballon Bleu references using 18mm to 22mm lug widths, natively supported with no adapter. Installation uses the standard spring-bar system - no modification to the watch, fully reversible in seconds.
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Cartier compatibility

Wear a smartwatch with your Cartier

In short Smartlet One is compatible with Cartier Santos, Tank, and Ballon Bleu references using 18mm to 22mm lug widths, natively supported with no adapter. Installation uses the standard spring-bar system - no modification to the watch, fully reversible in seconds.

Cartier invented the wristwatch and never forgot it. The Santos, the Tank, the Ballon Bleu - each case geometry has a century of recognition behind it. Wearing a Cartier is a choice about aesthetics as much as precision. Smartlet One does not compete with that choice. It attaches via the standard spring-bar mechanism and adds a smartwatch track on the same wrist. The guilloché dial, the blued hands, the signature crown - untouched.

Wear yours How it works
The problem
Choosing between health data and horological heritage every morning.
The solution
Smartlet One replaces your Cartier'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.
Brand
Cartier
Lug widths
18.0mm / 19.0mm / 20.0mm / 21.0mm / 22.0mm / 23.0mm / 24.0mm
Iconic models
2covered
Compatibility
Full range

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 models supported

Cartier Santos de Cartier Large
19mm / 20mm / 23mm / 24mm
Cartier Tank
18mm / 19mm / 20mm / 21mm / 22mm

Other Cartier references

31 model families. Expand any group to see variants, references, and specifications.

Astrocalendar
22mm1 refs+
ReferenceMaterialDialLugSmartlet
ASTROCAL-RG-201618K Pink GoldSilver22mmCompatible
Astroregulateur
22mm1 refs+
ReferenceMaterialDialLugSmartlet
PROTO-ASTRO-2012Carbon/SteelBlack22mmCompatible
Astrotourbillon
22mm2 refs+
ReferenceMaterialDialLugSmartlet
ASTRO-CARBON-2015Carbon/SteelBlack22mmCompatible
PROTO-ASTROCARB-2015Carbon/SteelBlack22mmCompatible
Ballon
19mm / 20mm3 refs+
ReferenceMaterialDialLugSmartlet
CPCP-BB-200518K Yellow GoldBlue Paris19mmCompatible
WHBB001818K White GoldSkeleton20mmCompatible
WHBB0007PlatinumSilver20mmCompatible
CPCP
18mm / 19mm / 20mm / 22mm5 refs+
ReferenceMaterialDialLugSmartlet
ROT-MONO-CPCP-200718K Rose GoldSilver22mmCompatible
TCT-CPCP-199918K Yellow GoldSilver20mmCompatible
TCHIN-CPCP-200418K Yellow GoldGuilloché18mmCompatible
TORT-MONO-CPCP-199818K Yellow GoldGuilloché19mmCompatible
TORT-QP-CPCP-200318K Pink GoldGuilloché Silver19mmCompatible
Calibre
22mm8 refs+
ReferenceMaterialDialLugSmartlet
W7100056Adlc SteelBlack22mmCompatible
W7100016Stainless SteelSilver22mmCompatible
W7100015Stainless SteelBlack22mmCompatible
W7100041Stainless SteelSilver22mmCompatible
W7100061Stainless SteelSilver22mmCompatible
W7100062Stainless SteelBlack22mmCompatible
W7100052Stainless SteelBlack22mmCompatible
W7100055Stainless SteelBlue22mmCompatible
Ceinture
18mm1 refs+
ReferenceMaterialDialLugSmartlet
CEINT-197318K Yellow GoldSilver18mmCompatible
Cintrée
20mm1 refs+
ReferenceMaterialDialLugSmartlet
CINT-1925-SAL18K Yellow GoldSalmon20mmCompatible
Concept
22mm2 refs+
ReferenceMaterialDialLugSmartlet
FT-CARBON-2014Carbon/SteelBlack22mmCompatible
PROTO-DIVER-2015Steel/CarbonBlack22mmCompatible
Crash
18mm2 refs+
ReferenceMaterialDialLugSmartlet
WHTA000818K Pink GoldSkeleton18mmCompatible
WHTA0009PlatinumSkeleton18mmCompatible
Drive
20mm9 refs+
ReferenceMaterialDialLugSmartlet
DRIVE-MP-PLAT-2018PlatinumSilver20mmCompatible
Drive-TB-WG-201918K White GoldSilver20mmCompatible
WGDR000618K Pink GoldSilver20mmCompatible
WSNM000818K Pink GoldSilver Moonphase20mmCompatible
WGNM000818K White GoldSilver20mmCompatible
WGNM0004Stainless SteelSilver20mmCompatible
WGNM0005Stainless SteelGrey20mmCompatible
WSNM0005Stainless SteelSilver Moonphase20mmCompatible
WSNM0011Stainless SteelSilver20mmCompatible
Grand
18mm1 refs+
ReferenceMaterialDialLugSmartlet
GCSW-201918K White GoldDiamond Pavé18mmCompatible
High
18mm1 refs+
ReferenceMaterialDialLugSmartlet
HJ-TORT-RNBW-202218K Pg/Rainbow GemsSilver18mmCompatible
ID
22mm2 refs+
ReferenceMaterialDialLugSmartlet
ID-ONE-2010Zirconia CeramicBlack22mmCompatible
ID-TWO-2012Transparent CeramystClear22mmCompatible
ID-One
22mm1 refs+
ReferenceMaterialDialLugSmartlet
IDONE-2010Zirconia CeramicBlack22mmCompatible
ID-Two
22mm1 refs+
ReferenceMaterialDialLugSmartlet
IDTWO-2012Transparent CeramystTransparent22mmCompatible
Japan-Only
19mm / 20mm2 refs+
ReferenceMaterialDialLugSmartlet
TL-JDM-BLU-201218K PgBlue19mmCompatible
TS-JDM-BLK-2018SteelBlack Roman20mmCompatible
Masse
20mm1 refs+
ReferenceMaterialDialLugSmartlet
WGMM0002PlatinumSkeleton Mystery20mmCompatible
Middle
19mm1 refs+
ReferenceMaterialDialLugSmartlet
TL-ME-GRN-202118K PgGreen Lacquer19mmCompatible
Minute
22mm2 refs+
ReferenceMaterialDialLugSmartlet
WSMR000518K Pink GoldSilver22mmCompatible
WSMR000418K White GoldSilver22mmCompatible
Mysterious
20mm1 refs+
ReferenceMaterialDialLugSmartlet
WHDA000118K Pink GoldSilver Day/Night20mmCompatible
One-of-One
18mm1 refs+
ReferenceMaterialDialLugSmartlet
HJ-COMET-2020Wg/Diamonds/SapphireMidnight Blue18mmCompatible
Pasha
18mm / 20mm / 22mm7 refs+
ReferenceMaterialDialLugSmartlet
W3001218K Yellow GoldSilver20mmCompatible
W31074M7Stainless SteelSilver20mmCompatible
WSPA0018Stainless SteelBlue20mmCompatible
WHPA000718K White GoldSkeleton22mmCompatible
W31088U2Stainless SteelSilver22mmCompatible
W31043M7Stainless SteelBlack18mmCompatible
W31030H3Stainless SteelSilver18mmCompatible
Pebble
18mm3 refs+
ReferenceMaterialDialLugSmartlet
PEBBLE-197218K Yellow GoldWhite Roman18mmCompatible
PEBBLE-202218K Yellow GoldWhite Roman18mmCompatible
PBB-PLAT-2023PlatinumSilver18mmCompatible
Prototype
20mm2 refs+
ReferenceMaterialDialLugSmartlet
PROTO-MH-2011Stainless SteelSilver20mmCompatible
PROTO-TANK-SKEL-2010SteelSkeleton20mmCompatible
Ronde
18mm / 20mm5 refs+
ReferenceMaterialDialLugSmartlet
WHRO0033PlatinumMysterious Silver20mmCompatible
W680015118K Yellow GoldSilver18mmCompatible
W900135218K White GoldSkeleton20mmCompatible
WSRN0002Stainless SteelSilver20mmCompatible
WSRN0003Stainless SteelSilver18mmCompatible
Rotonde
20mm / 22mm34 refs+
ReferenceMaterialDialLugSmartlet
WR007001-ACStainless SteelSilver20mmCompatible
WR007001Stainless SteelSilver20mmCompatible
WHRO003318K White GoldSilver Mysterious20mmCompatible
ASTRO-WG-201918K White GoldSilver20mmCompatible
WHAST0001PlatinumSilver22mmCompatible
WHR0N000518K Pink GoldSilver22mmCompatible
WHR0N000718K White GoldSkeleton22mmCompatible
WHRON0003PlatinumSilver22mmCompatible
WR007009Stainless SteelSilver Day/Night20mmCompatible
DAYNIGHT-PLAT-2015PlatinumSilver/Blue20mmCompatible
WHDT0001PlatinumSilver22mmCompatible
WTG0001PlatinumSilver22mmCompatible
WHRO001718K Pink GoldBlue Lunar22mmCompatible
WHRO001718K Pink GoldNavy/Silver22mmCompatible
WHRO0016PlatinumBlue Lunar22mmCompatible
WHRO0016PlatinumNavy/Silver22mmCompatible
W155621918K Pink GoldSilver20mmCompatible
W155621818K White GoldSilver20mmCompatible
WHRO0009PlatinumSilver22mmCompatible
WHRO0009PlatinumSilver22mmCompatible
WHRO0013PlatinumSilver22mmCompatible
LUN-ORB-WG-201818K WgNavy22mmCompatible
WHXR000218K Pink GoldSilver22mmCompatible
WHME0003PlatinumSilver22mmCompatible
W155623318K Pink GoldSilver20mmCompatible
WHRO000318K White GoldSilver20mmCompatible
WHDD0001PlatinumSilver22mmCompatible
WSRN0002Stainless SteelSilver20mmCompatible
RRPC-PT-2014PlatinumSilver20mmCompatible
SKE-ASTRO-2013White GoldSkeleton22mmCompatible
WHRO000518K White GoldSkeleton22mmCompatible
WHSA000918K White GoldSkeleton22mmCompatible
WHRA001618K White GoldSkeleton Panther20mmCompatible
MRSK-PLAT-2016PlatinumSkeleton22mmCompatible
Santos
20mm / 23mm / 24mm6 refs+
ReferenceMaterialDialLugSmartlet
W20106X8Stainless SteelWhite20mmCompatible
W20072X7Steel/Yellow GoldWhite23mmCompatible
W20073X8Stainless SteelWhite23mmCompatible
W20091X7Stainless SteelWhite24mmCompatible
WSSA0006Steel AdlcBlack23mmCompatible
WSSA0014Steel AdlcBlack23mmCompatible
Santos-Dumont
19mm / 20mm7 refs+
ReferenceMaterialDialLugSmartlet
WJSA001818K Pink GoldSilver19mmCompatible
WSSA0022Stainless SteelSilver19mmCompatible
W2SA0011Steel/Yellow GoldSilver19mmCompatible
WGSA005218K Pink GoldBurgundy Lacquer20mmCompatible
SDSM-MR-2023Titanium/SapphireSkeleton20mmCompatible
SD-TOKYO-2019SteelNavy Tokyo20mmCompatible
WGSA003218K Pink GoldSilver20mmCompatible
Special
19mm / 20mm / 21mm / 22mm4 refs+
ReferenceMaterialDialLugSmartlet
S0-SD-XL-201818K WgBlue Enamel20mmCompatible
SO-TORT-SAL-201918K Pink GoldSalmon19mmCompatible
SO-CINT-SAL-202018K Yellow GoldSalmon21mmCompatible
SO-TONNEAU-PLAT-2016PlatinumSilver22mmCompatible
Tortue
19mm / 20mm6 refs+
ReferenceMaterialDialLugSmartlet
TORT-1912-199818K Yellow GoldSilver19mmCompatible
TORT-CPCP-YG-199918K Yellow GoldGuilloché Silver19mmCompatible
TORT-MONO-200418K Pink GoldSilver19mmCompatible
TORT-MYS-RG-201518K Pink GoldSkeleton Mystery19mmCompatible
TORT-MYS-WG-201518K White GoldSkeleton Mystery19mmCompatible
PROTO-TORT-TB-201218K WgSilver20mmCompatible

Cartier lug widths:

18mm19mm20mm21mm22mm23mm24mm
Frequently paired

Smartwatches worn with Cartier

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

Smartlet One covers 18mm to 24mm lug widths across the finest watch brands.

Rolex
Omega
Tag Heuer
Breitling
Tudor
IWC
Longines
Seiko
Hamilton
Grand Seiko
Bell&Ross
Blancpain
Panerai
Jaeger Lecoultre
Zenith
Rado
Tissot
Oris
Doxa
Formex
Timex
Sinn
Porsche Design
Mido
Yema
Christopher Ward
View all
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 Cartier watches?
    Yes. Cartier references from 18mm to 24mm lug width are natively supported by Smartlet One.
  • Which Cartier models have guides?
    Santos de Cartier Large and Tank each have full reference tables with all variants and lug widths.
  • Will Smartlet affect the Cartier movement?
    No. Smartlet attaches via spring-bar slots. The case, crown, and movement are completely untouched.
  • Which recent Cartier releases work with Smartlet?
    Cartier's recent releases include the 2025 revival of the Tank a Guichets, the digital-display Tank first introduced in 1928. As always, any reference with standard spring bars between 18mm and 24mm lug width works with Smartlet.
  • 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.