Rolex Datejust & Fitbit Air on the same wrist

Rolex Datejust & Fitbit Air on the same wrist

The Rolex Datejust is compatible with Smartlet One, on watch adapters matching its 20mm / 21mm lug width. Fitbit Air support is coming soon, with a dedicated adapter. Once available, the Datejust sits on top of the wrist and the Air underneath, against the skin.
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Compatibility guide

Rolex Datejust & Fitbit Air on the same wrist

Rolex Datejust + Fitbit Air
The Rolex Datejust is compatible with Smartlet One, on watch adapters matching its 20mm / 21mm lug width. Fitbit Air support is coming soon, with a dedicated adapter. Once available, the Datejust sits on top of the wrist and the Air underneath, against the skin.
Rolex Datejust lug width
20mm / 21mm
Fitbit Air compatibility
Screenless tracker (2026)
Adapter
Dedicated Fitbit Air adapter, coming soon
Sensor position
Underneath the wrist

Why discreet professionals pair the Datejust with Fitbit Air

Is the Rolex Datejust compatible with Fitbit Air on Smartlet?

Compatible
The Rolex Datejust is compatible with Smartlet One, on watch adapters matching its 20mm / 21mm lug width. Fitbit Air support is coming soon, with a dedicated adapter. Once available, the Datejust sits on top of the wrist and the Air underneath, against the skin.
Rolex Datejust lug width
20mm / 21mm Supported
Watch adapters in the lug holes
Fitbit Air model
Screenless tracker (2026)
Dedicated Fitbit Air adapter, coming soon
Sensor position
Underneath the wrist
Against the skin
Reversible
Fully
No modification to the watch

Related compatibility guides

Model guide
Rolex Datejust
→
Brand guide
All Rolex models
→
Smartwatch guide
Fitbit Air compatibility
→

More ways to wear Smartlet

Rolex Datejust + Apple Watch
Rolex Datejust
→
Rolex Submariner + Fitbit Air
Rolex Submariner
→
Omega Speedmaster + Fitbit Air
Omega Speedmaster
→

Choose your Smartlet

Step by step

Replace your strap
01

Replace your strap

The watch adapters seat in your mechanical watch's lug holes in place of the spring bars. Classic, Shadow or Titanium. The spring bar tool is in the box.

Connect your wearable
02

Connect your wearable

Your smartwatch attaches to the central part of the bracelet with its own adapter (Apple Watch, Whoop, Fitbit, Galaxy or Pixel Watch) or a pair of standard watch adapters. Zero modification to the mechanical watch.

Wear both simultaneously
03

Wear both simultaneously

Both watches sit on the same wrist. The smartwatch sits underneath, against the skin.

Questions

Frequently asked questions

  • Which Datejust references work with Smartlet?
    References with 20mm / 21mm lug widths are covered, with watch adapters in the matching width. The Datejust model guide lists every reference.
  • Is the Fitbit Air visible when worn with the Datejust?
    Barely. The Air's thin, screenless profile sits on the inner wrist, under the cuff line. From across a table, you are wearing a Datejust.
  • Does the pairing work with a Jubilee bracelet Datejust?
    Yes: Smartlet replaces the bracelet, with watch adapters in place of the spring bars. Your Jubilee bracelet is kept and can go back on at any time.
  • Does Smartlet damage or modify my mechanical watch?
    No. The watch adapters seat in your watch's lug holes in place of the spring bars. Nothing is modified on the case, lugs or dial, and the change is fully reversible: your mechanical watch can go back on its original strap at any time.