Wear a smartwatch with your Sinn

Wear a smartwatch with your Sinn

Smartlet One is compatible with all Sinn 104, 556, and EZM references using 20mm 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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Sinn compatibility

Wear a smartwatch with your Sinn

In short Smartlet One is compatible with all Sinn 104, 556, and EZM references using 20mm 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.

Sinn makes tool watches in Frankfurt using aerospace materials and military-grade specifications. The 104 uses a tegimented steel case harder than standard 316L. The EZM series was developed with German special operations units. The argon-filled case prevents fogging. These are not features added for marketing - they address specific failure modes in demanding environments. Smartlet One was built with the same orientation: solve the problem of wearing two watches cleanly, via spring bars, without modification.

Wear yours How it works
The problem
Choosing between health data and horological heritage every morning.
The solution
Smartlet One replaces your Sinn'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
Sinn
Lug widths
20.0mm / 22.0mm
Iconic models
0covered
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 (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

Sinn models supported

Other Sinn references

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

103
20mm20 refs+
ReferenceMaterialDialLugSmartlet
SIN-103SAB-BL01SteelBlue Sunburst20mmCompatible
SIN-103SAB-GN01SteelGreen Sunburst20mmCompatible
SIN-103SAB-RD01SteelRed Sunburst20mmCompatible
SIN-103SAB-BR01SteelBrown20mmCompatible
SIN-103SAB-GR02SteelGrey Sunburst20mmCompatible
SIN-103SAB-CB01SteelCobalt20mmCompatible
SIN-103SAB-IB01SteelIce Blue20mmCompatible
SIN-103SAB-PP01SteelPurple20mmCompatible
SIN-103SAB-SD01SteelSand20mmCompatible
SIN-103SAB-SM01SteelSalmon20mmCompatible
SIN-103-BK01SteelBlack20mmCompatible
SIN-103-BL01SteelBlue20mmCompatible
SIN-103-WH01SteelWhite20mmCompatible
SIN-103-GN01SteelGreen20mmCompatible
SIN-103-RD01SteelRed20mmCompatible
SIN-103-GR01SteelGrey20mmCompatible
SIN-103SSA-BK01SteelBlack20mmCompatible
SIN-103SSA-WH01SteelWhite20mmCompatible
SIN-103TI-BK01TitaniumBlack20mmCompatible
SIN-103TI-BL01TitaniumBlue20mmCompatible
104
20mm10 refs+
ReferenceMaterialDialLugSmartlet
SIN-104-BK01SteelBlack20mmCompatible
SIN-104-WH01SteelWhite20mmCompatible
SIN-104-BL01SteelBlue20mmCompatible
SIN-104-GN01SteelGreen20mmCompatible
SIN-104-BR01SteelBrown20mmCompatible
SIN-104-GR01SteelGrey20mmCompatible
SIN-104-IB01SteelIce Blue20mmCompatible
SIN-104-RD01SteelRed20mmCompatible
SIN-104-CB01SteelCobalt20mmCompatible
SIN-104-PP01SteelPurple20mmCompatible
140
22mm20 refs+
ReferenceMaterialDialLugSmartlet
SIN-140-CB01SteelCobalt22mmCompatible
SIN-140-IB01SteelIce Blue22mmCompatible
SIN-140-PP01SteelPurple22mmCompatible
SIN-140-BK01SteelBlack22mmCompatible
SIN-140-WH01SteelWhite22mmCompatible
SIN-140-BL01SteelBlue22mmCompatible
SIN-140-GR01SteelGrey22mmCompatible
SIN-140-GN01SteelGreen22mmCompatible
SIN-140-RD01SteelRed22mmCompatible
SIN-140-BR01SteelBrown22mmCompatible
SIN-140-BO01SteelBlack/Orange22mmCompatible
SIN-140-CH01SteelChrome22mmCompatible
SIN-140-BS01SteelBlue Sunburst22mmCompatible
SIN-140-PVD01Pvd BlackBlack22mmCompatible
SIN-140-GNS01SteelGreen Sunburst22mmCompatible
SIN-140-SL01SteelSilver22mmCompatible
SIN-140-AW01SteelArctic White22mmCompatible
SIN-140-BRS01SteelBrown Sunburst22mmCompatible
SIN-140-CB02SteelCobalt Sunburst22mmCompatible
SIN-140-JD01SteelJade22mmCompatible
556
20mm20 refs+
ReferenceMaterialDialLugSmartlet
SIN-556A-BK01SteelBlack20mmCompatible
SIN-556A-WH01SteelWhite20mmCompatible
SIN-556A-BL01SteelBlue20mmCompatible
SIN-556A-GN01SteelGreen20mmCompatible
SIN-556A-GR01SteelGrey20mmCompatible
SIN-556A-SD01SteelSand20mmCompatible
SIN-556A-CB01SteelCobalt20mmCompatible
SIN-556A-SM01SteelSalmon20mmCompatible
SIN-556A-IB01SteelIce Blue20mmCompatible
SIN-556A-TL01SteelTeal20mmCompatible
SIN-556I-BK01Stainless SteelBlack20mmCompatible
SIN-556I-WH01SteelWhite20mmCompatible
SIN-556I-BL01SteelBlue Sunburst20mmCompatible
SIN-556I-RD01SteelRed20mmCompatible
SIN-556I-GN01SteelGreen Sunburst20mmCompatible
SIN-556I-AN01SteelAnthracite20mmCompatible
SIN-556I-CP01SteelCopper20mmCompatible
SIN-556I-YL01SteelYellow20mmCompatible
SIN-556I-IB01SteelIce Blue20mmCompatible
SIN-556I-PP01SteelPurple20mmCompatible
756
20mm5 refs+
ReferenceMaterialDialLugSmartlet
SIN-756-DP-BK01Steel TegimentedBlack20mmCompatible
SIN-756-DP-GR01Tegiment SteelGrey20mmCompatible
SIN-756-DP-BL01Tegiment SteelBlue20mmCompatible
SIN-756-DP-WH01Tegiment SteelWhite20mmCompatible
SIN-756-DP-BR01Tegiment SteelBrown20mmCompatible
757
22mm5 refs+
ReferenceMaterialDialLugSmartlet
SIN-757-UTC-BK01SteelBlack22mmCompatible
SIN-757-UTC-BL01SteelBlue22mmCompatible
SIN-757-UTC-WH01SteelWhite22mmCompatible
SIN-757-UTC-GN01SteelGreen22mmCompatible
SIN-757-UTC-GR01SteelGrey22mmCompatible
856
20mm10 refs+
ReferenceMaterialDialLugSmartlet
SIN-856-UTC-BK01Tegiment SteelBlack20mmCompatible
SIN-856-UTC-BL01Tegiment SteelBlue20mmCompatible
SIN-856-UTC-GN01Tegiment SteelGreen20mmCompatible
SIN-856-UTC-GR01Tegiment SteelGrey20mmCompatible
SIN-856-UTC-WH01Tegiment SteelWhite20mmCompatible
SIN-856-UTC-SD01Tegiment SteelSand20mmCompatible
SIN-856-UTC-CB01Tegiment SteelCobalt20mmCompatible
SIN-856-UTC-PP01Tegiment SteelPurple20mmCompatible
SIN-856-UTC-BR01Tegiment SteelBrown20mmCompatible
SIN-856-UTC-IB01Tegiment SteelIce Blue20mmCompatible
857
22mm10 refs+
ReferenceMaterialDialLugSmartlet
SIN-857-UTC-BK01SteelBlack22mmCompatible
SIN-857-UTC-BL01SteelBlue22mmCompatible
SIN-857-UTC-WH01SteelWhite22mmCompatible
SIN-857-UTC-GR01SteelGrey22mmCompatible
SIN-857-UTC-GN01SteelGreen22mmCompatible
SIN-857-UTC-RD01SteelRed22mmCompatible
SIN-857-UTC-CB01SteelCobalt22mmCompatible
SIN-857-UTC-IB01SteelIce Blue22mmCompatible
SIN-857-UTC-BR01SteelBrown22mmCompatible
SIN-857-UTC-PP01SteelPurple22mmCompatible
Atelier
20mm / 22mm7 refs+
ReferenceMaterialDialLugSmartlet
UNQ-SIN-556-ENBLWhite GoldEnamel Blue20mmCompatible
UNQ-SIN-EZM-METGYellow GoldMeteorite22mmCompatible
UNQ-SIN-104-RUBRose GoldRuby20mmCompatible
UNQ-SIN-103-SKSSapphireSkeleton20mmCompatible
UNQ-SIN-U50-METSubmarine SteelMeteorite20mmCompatible
UNQ-SIN-U1-DRGSubmarine SteelEngraved Dragon22mmCompatible
UNQ-SIN-EZM-JDTegiment SteelJade22mmCompatible
EZM
20mm / 22mm20 refs+
ReferenceMaterialDialLugSmartlet
SIN-EZM11-BK01SteelBlack22mmCompatible
SIN-EZM11-GR01SteelGrey22mmCompatible
SIN-EZM11-WH01SteelWhite22mmCompatible
SIN-EZM11-BL01SteelBlue22mmCompatible
SIN-EZM11-GN01SteelGreen22mmCompatible
SIN-EZM11-IB01SteelIce Blue22mmCompatible
SIN-EZM11-RD01SteelRed22mmCompatible
SIN-EZM11-CB01SteelCobalt22mmCompatible
SIN-EZM11-PP01SteelPurple22mmCompatible
SIN-EZM11-SD01SteelSand22mmCompatible
SIN-EZM3-BK01SteelBlack20mmCompatible
SIN-EZM3-BL01SteelBlue20mmCompatible
SIN-EZM3-GN01SteelGreen20mmCompatible
SIN-EZM3-RD01SteelRed20mmCompatible
SIN-EZM3-AW01SteelArctic White20mmCompatible
SIN-EZM3-GR01SteelGrey20mmCompatible
SIN-EZM3-IB01SteelIce Blue20mmCompatible
SIN-EZM3-CB01SteelCobalt20mmCompatible
SIN-EZM3-PP01SteelPurple20mmCompatible
SIN-EZM3-BR01SteelBrown20mmCompatible
Finanzplatzuhr
20mm10 refs+
ReferenceMaterialDialLugSmartlet
SIN-FP6000-BK01SteelBlack20mmCompatible
SIN-FP6000-WH01SteelWhite20mmCompatible
SIN-FP6000-BL01SteelBlue20mmCompatible
SIN-FP6000-GR01SteelGrey20mmCompatible
SIN-FP6000-GN01SteelGreen20mmCompatible
SIN-FP6000-SM01SteelSalmon20mmCompatible
SIN-FP6000-CB01SteelCobalt20mmCompatible
SIN-FP6000-IB01SteelIce Blue20mmCompatible
SIN-FP6000-BR01SteelBrown20mmCompatible
SIN-FP6000-PP01SteelPurple20mmCompatible
Prototype
20mm / 22mm3 refs+
ReferenceMaterialDialLugSmartlet
P-SIN-103-CERCeramicBlack20mmCompatible
P-SIN-EZM-TITitaniumGrey22mmCompatible
P-SIN-U1-SAPSapphireTransparent22mmCompatible
U1
22mm10 refs+
ReferenceMaterialDialLugSmartlet
SIN-U1-BK01Submarine SteelBlack22mmCompatible
SIN-U1-BL01Submarine SteelBlue22mmCompatible
SIN-U1-BR01Submarine SteelBrown22mmCompatible
SIN-U1-CB01Submarine SteelCobalt22mmCompatible
SIN-U1-GN01Submarine SteelGreen22mmCompatible
SIN-U1-GR01Submarine SteelGrey22mmCompatible
SIN-U1-IB01Submarine SteelIce Blue22mmCompatible
SIN-U1-PP01Submarine SteelPurple22mmCompatible
SIN-U1-RD01Submarine SteelRed22mmCompatible
SIN-U1-WH01Submarine SteelWhite22mmCompatible
U50
20mm10 refs+
ReferenceMaterialDialLugSmartlet
SIN-U50-BK01Submarine SteelBlack20mmCompatible
SIN-U50-CB01Submarine SteelCobalt20mmCompatible
SIN-U50-GN01Submarine SteelGreen20mmCompatible
SIN-U50-GR01Submarine SteelGrey20mmCompatible
SIN-U50-IB01Submarine SteelIce Blue20mmCompatible
SIN-U50-PP01Submarine SteelPurple20mmCompatible
SIN-U50-RD01Submarine SteelRed20mmCompatible
SIN-U50-SM01Submarine SteelSalmon20mmCompatible
SIN-U50-SD01Submarine SteelSand20mmCompatible
SIN-U50-WH01Submarine SteelWhite20mmCompatible
UX
22mm10 refs+
ReferenceMaterialDialLugSmartlet
SIN-UX-BK01SteelBlack22mmCompatible
SIN-UX-BL01SteelBlue22mmCompatible
SIN-UX-WH01SteelWhite22mmCompatible
SIN-UX-GR01SteelGrey22mmCompatible
SIN-UX-GN01SteelGreen22mmCompatible
SIN-UX-RD01SteelRed22mmCompatible
SIN-UX-IB01SteelIce Blue22mmCompatible
SIN-UX-CB01SteelCobalt22mmCompatible
SIN-UX-PP01SteelPurple22mmCompatible
SIN-UX-BR01SteelBrown22mmCompatible

Sinn lug widths:

20mm22mm
Frequently paired

Smartwatches worn with Sinn

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

Apple Watch
Series 0 to Ultra 3
¡Vaya!
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
Cartier
Jaeger-LeCoultre
Zenith
Rado
Tissot
Oris
Doxa
Formex
Timex
Porsche Design
Mido
Yema
Christopher Ward
Ver todo
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 Sinn watches?
    Yes. Sinn references from 20mm to 22mm lug width are natively supported by Smartlet One.
  • Will Smartlet affect Sinn's special case treatments?
    No. Smartlet attaches via the spring-bar slots. Tegiment hardening, HYDRO technology, and oil-filled cases are unaffected.
  • Which Sinn references are compatible?
    All 20mm and 22mm references - 556, 140 St, 857, EZM series, U1 - 170+ references covered.
  • ¿Smartlet daña o modifica mi reloj mecánico?
    No. Smartlet reemplaza tu correa de reloj estándar utilizando el sistema de pasador de resorte existente. No realiza ninguna modificación permanente en la caja, asas o esfera del reloj. El proceso es completamente reversible en segundos. Tu reloj mecánico no se ve afectado y puede usarse de forma independiente en cualquier momento reinstalando su correa original. Smartlet está diseñado con tolerancias de relojero y probado con el mismo cuidado que se dedica a los relojes con los que se empareja.