Wear your Whoop and your mechanical watch at the same time

Wear your Whoop and your mechanical watch at the same time

Smartlet is compatible with Whoop 5.0 and Whoop MG via the dedicated MG adapter included in every box. All health sensors including HRV, SpO2, sleep and respiratory remain fully operational. The setup takes under two minutes and is fully reversible.
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Whoop compatibility

Wear your Whoop and your mechanical watch at the same time

In short Smartlet is compatible with Whoop 5.0 and Whoop MG via the dedicated MG adapter included in every box. All health sensors including HRV, SpO2, sleep and respiratory remain fully operational. The setup takes under two minutes and is fully reversible.

Whoop 5.0 and MG are purpose-built for recovery science: continuous HRV tracking, strain coaching, sleep staging, respiratory rate, blood oxygen. No screen, no notifications, no distractions. Smartlet positions your Whoop on the same wrist as your mechanical watch via a dedicated adapter included in every Smartlet box. You keep your horological heritage on display and your health data running underneath.

The problem
Choosing between health data and horological heritage every morning.
The solution
Smartlet replaces your mechanical watch strap and positions your Whoop on the same wrist via the dedicated MG adapter included in every box. Wear both simultaneously, without compromise to your watch or your health tracking.
Models
5.0 / MG
Lug width
Adapter included
Sensors
Continuous HRV +
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

Whoop models supported

Whoop 5.0 / MG
Compatible
Smartlet is compatible with Whoop 5.0 and Whoop MG via the dedicated Whoop adapter included in the Smartlet box. Whoop 4.0 (2021) is not supported due to the different connector geometry. All Whoop health sensors remain fully operational with full skin contact maintained at all times.
All Whoop sensors remain fully operational

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

Continuous HRVSpO2Strain coachingSleep stagingRespiratory rate

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 Whoop and a mechanical watch at the same time?
    Yes. Smartlet makes it possible to wear your Whoop and a mechanical watch simultaneously on the same wrist. Smartlet replaces your mechanical watch strap via the standard spring-bar system and holds your Whoop against the same wrist using the dedicated MG adapter included in every box. Both watches run at the same time. All Whoop health sensors maintain full skin contact and operate normally. You no longer have to choose between your health data and your mechanical watch every morning.
  • Which Whoop models are compatible with Smartlet?
    Smartlet is compatible with Whoop 5.0 and Whoop MG. The Whoop uses a proprietary connector, and a dedicated MG adapter included in Smartlet box bridges it to the Smartlet module. Setup takes under two minutes and requires no tools. Whoop 4.0 (2021) is not supported due to the different connector geometry. 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 Whoop sensors still work when used with Smartlet?
    Yes, all sensors remain fully operational. Smartlet positions the Whoop against your wrist with full skin contact maintained at all times. The following sensors continue to function normally: continuous HRV monitoring, strain coaching, sleep staging, respiratory rate tracking, and blood oxygen (SpO2). There is no interference with the sensor array, and health data accuracy is unaffected. The Smartlet adapter is engineered to position the Whoop sensor surface at the same skin pressure as the original Whoop band.
  • 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.