Tudor Black Bay & Fitbit Charge on the same wrist

Tudor Black Bay & Fitbit Charge on the same wrist

Yes. The Tudor Black Bay is compatible with Smartlet One, on watch adapters matching its 19mm / 20mm / 21mm / 22mm lug width. The Fitbit Charge 5 and 6 adapters are in the box. The Black Bay sits on top of the wrist; the Charge sits underneath, against the skin. Google does not certify readings taken in this position.
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Compatibility guide

Tudor Black Bay & Fitbit Charge on the same wrist

Tudor Black Bay + Fitbit Charge
Yes. The Tudor Black Bay is compatible with Smartlet One, on watch adapters matching its 19mm / 20mm / 21mm / 22mm lug width. The Fitbit Charge 5 and 6 adapters are in the box. The Black Bay sits on top of the wrist; the Charge sits underneath, against the skin. Google does not certify readings taken in this position.
Tudor Black Bay lug width
19mm / 20mm / 21mm / 22mm
Fitbit Charge compatibility
Charge 5 / 6
Adapter
Fitbit Charge adapters in the box
Sensor position
Underneath the wrist

Why value-minded enthusiasts pair the Black Bay with Fitbit Charge

Is the Tudor Black Bay compatible with Fitbit Charge on Smartlet?

Compatible
Yes. The Tudor Black Bay is compatible with Smartlet One, on watch adapters matching its 19mm / 20mm / 21mm / 22mm lug width. The Fitbit Charge 5 and 6 adapters are in the box. The Black Bay sits on top of the wrist; the Charge sits underneath, against the skin. Google does not certify readings taken in this position.
Tudor Black Bay lug width
19mm / 20mm / 21mm / 22mm Supported
Watch adapters in the lug holes
Fitbit Charge model
Charge 5 / 6
Fitbit Charge adapters in the box
Sensor position
Underneath the wrist
Not certified by Google in this position
Reversible
Fully
No modification to the watch

Related compatibility guides

Model guide
Tudor Black Bay
→
Brand guide
All Tudor models
→
Smartwatch guide
Fitbit Charge compatibility
→

More ways to wear Smartlet

Tudor Black Bay + Apple Watch
Tudor Black Bay
→
Seiko 5 + Fitbit Charge
Seiko 5
→
Seiko Prospex + Fitbit Charge
Seiko Prospex
→

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; readings taken there are not certified by its manufacturer.

Questions

Frequently asked questions

  • Which Black Bay references work with Smartlet?
    References with 18mm / 20mm / 22mm lug widths are covered, with watch adapters in the matching width. The Black Bay model guide lists every reference, including the 41's 22mm.
  • Does the 22mm Black Bay 41 need a special adapter?
    No. Smartlet takes lug widths from 18mm to 24mm (23mm coming soon), so the Black Bay 41 fits with 22mm watch adapters.
  • Will the Charge's sleep tracking work on the inner wrist?
    The sensors face the skin underneath the wrist, and the bracelet is sized by its links so the Fitbit Charge sits snug. Google does not certify readings taken in this position: for a reading with medical weight, put the Fitbit Charge back on its own band and follow Google's instructions. Notifications and the other functions work as usual.
  • 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.