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, with the Fitbit Charge adapter included in the box. The Black Bay mounts via its 18mm / 20mm / 22mm lug width; the Charge keeps full skin contact on the inner wrist with all tracking operational.
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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, with the Fitbit Charge adapter included in the box. The Black Bay mounts via its 18mm / 20mm / 22mm lug width; the Charge keeps full skin contact on the inner wrist with all tracking operational.
Tudor Black Bay lug width
18mm / 20mm / 22mm
Fitbit Charge compatibility
Charge 5 / 6
Adapter
Adapter included in every Smartlet box
Sensor accuracy
Fully maintained

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

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

Compatible
Yes. The Tudor Black Bay is compatible with Smartlet One, with the Fitbit Charge adapter included in the box. The Black Bay mounts via its 18mm / 20mm / 22mm lug width; the Charge keeps full skin contact on the inner wrist with all tracking operational.
Tudor Black Bay lug width
18mm / 20mm / 22mm Supported
Standard spring-bar system
Fitbit Charge model
Charge 5 / 6
Adapter included in every Smartlet box
Sensor accuracy
Fully maintained
Inner wrist position
Reversible
In seconds
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
→

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

  • Which Black Bay references work with Smartlet?
    References across 18mm / 20mm / 22mm lug widths are covered via the standard spring-bar system; 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 natively supports lug widths from 18mm to 24mm, so the 22mm Black Bay 41 mounts directly via its spring bars.
  • Will the Charge's sleep tracking work on the inner wrist?
    Yes. The position maintains the constant skin contact optical sensors require, so sleep stages and heart rate track normally.
  • 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.