Wear your Apple Watch and your mechanical watch at the same time

Wear your Apple Watch and your mechanical watch at the same time

Smartlet is compatible with the Apple Watch Series 0 to Ultra 3 with no adapter required. All health sensors remain fully operational with full skin contact maintained at all times. The setup takes under two minutes and is fully reversible.
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Apple Watch compatibility

Wear your Apple Watch and your mechanical watch at the same time

In short Smartlet is compatible with the Apple Watch Series 0 to Ultra 3 with no adapter required. All health sensors remain fully operational with full skin contact maintained at all times. The setup takes under two minutes and is fully reversible.

The Apple Watch is the world's most advanced health companion: ECG, SpO2, crash detection, sleep staging, skin temperature. Smartlet positions your Apple Watch on the same wrist as your mechanical watch, with every sensor in full skin contact and every function intact.

Wear yours How it works
The problem
Choosing between health data and horological heritage every morning.
The solution
Smartlet replaces your mechanical watch strap and positions your Apple Watch on the same wrist with no adapter required. Wear both simultaneously, without compromise to your watch or your health tracking.
Models
Series 0 to Ultra 3
Lug width
mm
Sensors
ECG +
Reversible
In seconds
Gallery

Apple Watch with Smartlet

Smartlet One - Classic - Smartlet
life:Smartlet One - Classic - Smartlet
life:Smartlet One - Classic - Smartlet
life:Smartlet One - Classic - Smartlet
life:Smartlet One - Classic - Smartlet
life:Smartlet One - Classic - Smartlet
Smartlet One - Classic - Smartlet
Smartlet One - Shadow - Smartlet
life:Smartlet One - Shadow - Smartlet
life:Smartlet One - Shadow - Smartlet
life:Smartlet One - Shadow - Smartlet
life:Smartlet One - Shadow - Smartlet
life:Smartlet One - Shadow - Smartlet
life:Smartlet One - Shadow - Smartlet
Smartlet One - Shadow - Smartlet
Smartlet One - Titanium - Smartlet
life:Smartlet One - Titanium - Smartlet
life:Smartlet One - Titanium - Smartlet
life:Smartlet One - Titanium - Smartlet
life:Smartlet One - Titanium - Smartlet
life:Smartlet One - Titanium - Smartlet
life:Smartlet One - Titanium - Smartlet
Smartlet One - Titanium - Smartlet

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 (16)

Stealth. Switch in seconds, leave no trace.

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

Apple Watch models supported

Apple Watch Series 0 to Ultra 3
Compatible
Smartlet is compatible with every Apple Watch model from Series 0 to Ultra 3. All Apple Watch bands use a 20mm attachment width, natively supported. The Apple Watch slides into the Smartlet module in seconds with all sensors fully operational and full skin contact maintained at all times.
All Apple Watch sensors remain fully operational

Smartlet positions your wearable with full skin contact maintained at all times. Health data accuracy is unaffected.

ECGSpO2Heart rateCrash detectionSleep stagingSkin temperature
Frequently paired

Mechanical watches worn with Apple Watch

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

Rolex
Rolex Cosmograph Daytona·Rolex Datejust 41·Rolex Explorer·Rolex GMT-Master II
18.0mm / 19.0mm / 20.0mm / 21.0mm / 22.0mm / 23.0mm
Omega
Omega Aqua Terra·Omega Constellation Co-Axial·Omega De Ville Tresor·Omega Seamaster 300M
18.0mm / 19.0mm / 20.0mm / 21.0mm / 22.0mm / 23.0mm
Tudor
Tudor Black Bay 41·Tudor Pelagos 42·Tudor Ranger·Tudor Monarch
18.0mm / 19.0mm / 20.0mm / 22.0mm
TAG Heuer
TAG Heuer Aquaracer Professional 300·TAG Heuer Carrera Chronograph 42·TAG Heuer Formula 1·TAG Heuer Monaco
18.0mm / 19.0mm / 20.0mm / 21.0mm / 22.0mm
Seiko
Seiko Presage·Seiko Prospex SPB143·Seiko SKX Diver·Seiko Seiko 5
18.0mm / 19.0mm / 20.0mm / 21.0mm / 22.0mm / 23.0mm / 24.0mm
Breitling
Breitling Avenger·Breitling Navitimer B01 43·Breitling Superocean Automatic
20.0mm / 21.0mm / 22.0mm / 24.0mm
IWC
IWC Big Pilot·IWC Portugieser Automatic 40
18.0mm / 20.0mm / 21.0mm / 22.0mm
View all brands
27 brands covered
Combination guides

Wear it both ways

Omega Seamaster 300M + Apple Watch
Omega Seamaster 300M
→
Omega Speedmaster Moonwatch + Apple Watch
Omega Speedmaster Moonwatch
→
Rolex Datejust 41 + Apple Watch
Rolex Datejust 41
→
Rolex Cosmograph Daytona + Apple Watch
Rolex Cosmograph Daytona
→
Rolex GMT-Master II + Apple Watch
Rolex GMT-Master II
→
Rolex Submariner + Apple Watch
Rolex Submariner
→
Tudor Black Bay 41 + Apple Watch
Tudor Black Bay 41
→
Tudor Monarch + Apple Watch
Tudor Monarch
→
Also compatible

Other smartwatches

Smartlet works with all major smartwatches via dedicated adapters or native lug widths.

Samsung Galaxy Watch
Garmin Forerunner
Polar Vantage
Google Pixel Watch
Huawei Watch GT
Fitbit Charge
Fitbit Air
Whoop
Garmin Venu
Withings Scanwatch
Coros
Suunto
Panther Eclipse
View all
Smartwatch 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

  • Can I wear a Apple Watch and a mechanical watch at the same time?
    Yes. Smartlet makes it possible to wear your Apple Watch and a mechanical watch simultaneously on the same wrist. Smartlet replaces your mechanical watch strap via the standard spring-bar system and holds your Apple Watch against the same wrist. Both watches run at the same time. All Apple Watch health sensors maintain full skin contact and operate normally. You no longer have to choose between health data and your mechanical watch every morning.
  • Which Apple Watch models are compatible with Smartlet?
    Smartlet is compatible with the Apple Watch Series 0 to Ultra 3. All Apple Watch bands use a 20mm attachment width, natively supported by the Smartlet module. Setup takes under two minutes and requires no tools. Smartlet is compatible with any mechanical watch between 18mm and 24mm lug width, covering the vast majority of the market including Rolex, Omega, Tudor, TAG Heuer, Seiko, Breitling, and IWC.
  • Will Apple Watch sensors still work when used with Smartlet?
    Yes, all sensors remain fully operational. Smartlet positions the Apple Watch against your wrist with full skin contact maintained at all times. The following sensors continue to function normally: ECG, spo2, heart rate, crash detection, sleep staging, skin temperature. There is no interference with the sensor array, and health data accuracy is unaffected.
  • 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.