Wear a smartwatch with your Zenith El Primero

Wear a smartwatch with your Zenith El Primero

Smartlet is compatible with all Zenith El Primero references. Lug widths range from 19mm to 22mm - all natively supported with no adapter. Installation uses the standard spring-bar system - no modification to the watch, fully reversible in seconds.
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Zenith El Primero compatibility

Wear a smartwatch with your Zenith El Primero

In short Smartlet is compatible with all Zenith El Primero references. Lug widths range from 19mm to 22mm - all natively supported with no adapter. Installation uses the standard spring-bar system - no modification to the watch, fully reversible in seconds.

Smartlet is compatible with all Zenith El Primero references. Lug widths range from 19mm to 22mm - all natively supported with no adapter. Installation uses the standard spring-bar system - no modification to the watch, fully reversible in seconds.

Wear yours How it works
The problem
Choosing between health data and horological heritage every morning.
The solution
Smartlet One replaces your Zenith El Primero's strap via the standard spring-bar system and positions your smartwatch on the same wrist. Both watches run simultaneously, with no modification to the watch and full reversibility in seconds.
Model
Zenith El Primero
Lug width
19mm / 20mm / 21mm / 22mm
References
20covered
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 (14)

Stealth. Switch in seconds, leave no trace.

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

Zenith El Primero models supported

Covered references

20 references covered.

ReferenceMaterialDialLugSmartlet
18.2120.679/01.C498Rose Gold 38mmSilver20mmCompatible
Cal.146D-1960Stainless Steel 38mmWhite19mmCompatible
Cal.146D-1962Stainless Steel 38mmBlack19mmCompatible
146H-1963Stainless Steel 38mmSilver19mmCompatible
Proto-EP36000Stainless Steel 38mmBlack19mmCompatible
A384 Revival 50thStainless Steel 38mmPanda19mmCompatible
A385 Revival 50thStainless Steel 38mmBrown Gradient19mmCompatible
A386 Revival 50thStainless Steel 38mmTri-Color19mmCompatible
A384Stainless Steel 38mmWhite/Black Panda19mmCompatible
A385Stainless Steel 38mmBrown Gradient19mmCompatible
A386Stainless Steel 38mmTri-Color19mmCompatible
01.0043.400Stainless Steel 38mmBlack20mmCompatible
02.2310.400Stainless Steel 38mmWhite Panda20mmCompatible
01.2310.400Stainless Steel 38mmBlack Panda20mmCompatible
02.0470.400Stainless Steel 38mmBlack20mmCompatible
03.1260.4039Stainless Steel 42mmBlack Open22mmCompatible
18.2050.4021Rose Gold 42mmSilver Open21mmCompatible
03.2050.4021Stainless Steel 42mmBlack Open21mmCompatible
03.2061.405/69.M2060Stainless Steel 42mmBlack22mmCompatible
03.2066.405/69.R515Stainless Steel 42mmBlack22mmCompatible

Zenith El Primero lug widths: 19mm / 20mm / 21mm / 22mm

Frequently paired

Smartwatches worn with Zenith El Primero

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

Apple Watch
Series 0 to Ultra 3
Whoop
5.0 / MG
Garmin Forerunner
255 to 965
Samsung Galaxy Watch
Series 4 to 7
Withings ScanWatch
Light / 2 / Nova
View all brands
27 brands covered
Also compatible

Other brands

Other iconic models in the Smartlet compatibility library.

Submariner
Daytona
GMT-Master
Datejust
Yacht-Master
Sky-Dweller
Explorer
Seamaster 300m
Speedmaster
Planet Ocean
Constellation
De Ville
Monaco
Carrera
Formula 1
Aquaracer
Portugieser
Navitimer
Superocean
Avenger
Black Bay
Pelagos
Ranger
Luminor
Radiomir
Submersible
SKX
Prospex
Presage
Khaki Field
BR 03-92
Fifty Fathoms
Reverso
SUB 300
Spring Drive
Essence Leggera
Aquis
Divers Sixty-Five
Chronograph 1
Captain Cook
Superman Heritage
Monarch
Black Bay 58 GMT
View all models
Watch brand 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

  • Is Smartlet compatible with the Zenith El Primero?
    Yes. El Primero references use 19mm to 22mm lugs - all natively supported. No adapter required. The El Primero 400 calibre is completely unaffected.
  • Does Smartlet affect the El Primero movement?
    No. Smartlet attaches via standard spring bars. The column wheel chronograph mechanism running at 36,000 vph is not touched.
  • Which El Primero lug width fits Smartlet?
    All of them. The A386 Revival at 19mm, Chronomaster Original at 19mm, and Sport references at 22mm are all natively supported.
  • Does Smartlet work with the Zenith El Primero?
    Yes. El Primero references use 19mm to 22mm lugs, all natively supported by Smartlet. No adapter required.
  • 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.