Smartwatch Compatibility Guide | Wear Any Smartwatch with Your Watch | Smartlet

 

Kompatibilität mit Smartwatches

Wear any smartwatch
with any mechanical watch

Smartlet One is a modular adapter that clips any smartwatch onto any mechanical watch strap. Compatible with all standard lug widths from 18mm to 24mm. All sensors remain fully operational. No tools, no modifications, fully reversible.

13+
Brands with full guides
100+
Models compatible
18-24mm
Native lug range
0
Tools required
All supported smartwatches

Choose your smartwatch

Select your smartwatch to see the full compatibility guide, model list, and sensor information.

Compatible
Apple
Apple Watch
Series 0 to 11 - SE - Ultra - Ultra 3
ECG, SpO2, heart rate, skin temperature, crash detection
Compatible
Samsung
Galaxy Watch
Watch 4 - 5 - 6 - 7 - Ultra
ECG, BIA body composition, SpO2, heart rate
Compatible
Garmin
Fenix
Fenix 6 - 7 - 8 (S and X variants)
Pulse Ox, heart rate, VO2 max, body battery, GPS
Compatible
Garmin
Forerunner
FR 255 - 265 - 955 - 965
Pulse Ox, heart rate, HRV, training readiness
Compatible
Polar
Vantage
Vantage M2 - V2 - V3
10-LED heart rate, HRV, SpO2, orthostatic test
Compatible
Google
Pixel Watch
Pixel Watch 1 - 2 - 3 (41mm & 45mm)
ECG, SpO2, heart rate, skin temperature, Fitbit
Compatible
Huawei
Watch GT
GT 3 - GT 4 - GT 5 - GT 5 Pro
ECG, SpO2, TruSeen heart rate, skin temperature
Compatible
Fitbit
Charge
Charge 5 - Charge 6
ECG, EDA stress, SpO2, sleep staging
Compatible
Whoop
Whoop 5.0 / MG
Whoop 5.0 - Whoop MG
HRV, heart rate, SpO2, respiratory rate, skin temp
Compatible
Garmin
Venu
Venu 2 - 2 Plus - 3 - Sq 2
SpO2, heart rate, HRV, body battery, sleep
Compatible
Withings
ScanWatch
ScanWatch - Light - 2 - Nova
ECG, AFib detection, SpO2, breathing disturbances
Compatible
Coros
Coros
Apex 2 - Apex 2 Pro - Pace 3 - Vertix 2
Heart rate, SpO2, HRV, EvoLab, multi-band GPS
Compatible
Suunto
Suunto
9 Peak - Race - Race S - Vertical
Heart rate, SpO2, HRV, barometric altimeter
So funktioniert es

Three steps. No compromise.

Smartlet works with all mechanical watches from 18mm to 24mm lug width, and all smartwatches listed above.

01
Choose your finish

Classic (brushed steel), Shadow (black PVD), or Titanium. Match your mechanical watch case material and aesthetic. No tools required at this stage.

02
Clip in your watch

Attach the Smartlet adapter to your watch lugs. The spring-loaded mechanism locks in place with zero metal-to-metal case contact. Fully reversible in seconds.

03
Clip in your smartwatch

Insert your smartwatch into the Smartlet module. It locks securely. Both watches now sit on the same wrist. All smartwatch sensors maintain direct skin contact and operate normally.

The universal rule: any metal watch, 18 to 24mm
Smartlet is compatible with any smartwatch using a standard band attachment between 18mm and 24mm, natively and without any adapter. Models with 26mm lugs are not compatible with Smartlet. Some smartwatches use proprietary band systems: a conversion adapter is then required from 3rd-party sellers. Smartlet does not sell these adapters directly. If your smartwatch has a standard lug width in the 18-24mm range, it works.
18-24mm - native, no adapter 26mm not compatible  Proprietary band - conversion adapter required
Extended compatibility

All compatible smartwatches

Dedicated guides exist for the 13 brands above. The list below covers every other smartwatch brand that works with Smartlet - natively or via adapter. A standard lug width between 18mm and 24mm is all that is required.

Native (18-24mm) Not compatible (26mm) Conversion adapter required Not compatible

Amazfit
GTR 4, GTS 4, Falcon, T-Rex Ultra, Balance, Cheetah Pro
20mm / 22mm

Garmin Instinct
Instinct 2, Instinct 2X Solar, Instinct Crossover
22mm
26mm variants: not compatible

Garmin Epix
Epix Gen 2, Epix Pro 42 / 47 / 51mm
20mm / 22mm
51mm (26mm lug): not compatible

Fossil
Gen 6, Gen 6 Wellness, Hybrid HR
18mm / 20mm / 22mm

Mobvoi TicWatch
Pro 5 GPS, Pro 3 Ultra, E3
22mm

Xiaomi
Watch S3, Watch 2 Pro, Watch Color 2
22mm

OnePlus Watch
Watch 2, Watch 2R
22mm

Polar Grit
Grit X2 Pro, Grit X
22mm

Polar Ignite
Ignite 3, Ignite 2
20mm

Polar Pacer
Pacer, Pacer Pro
20mm / 22mm

Huawei Band
Band 8, Band 9
18 mm

Honor Watch
Watch 4 Pro, Watch GS 3
20mm / 22mm

Oppo Watch
Watch 4 Pro, Watch X
22mm

Realme Watch
Watch 3 Pro, Watch S Pro
22mm

TAG Heuer Connected
Calibre E4 45mm, Golf Edition
22mm

Montblanc Summit
Summit 3, Summit Lite
22mm

Tissot T-Touch
T-Touch Connect Solar
21 mm

Kospet Tank
Tank T3 Ultra, Tank Pro 2
24 mm
26mm variant: not compatible

Casio G-Shock
GBD-H2000, DW-H5600, GM-B2100
20mm
Proprietary band on most models, conversion adapter required
Questions

Frequently asked

What lug widths does Smartlet support?+

Smartlet One natively accommodates any smartwatch band attachment from 18mm to 24mm, with no adapter required. This covers the vast majority of the market: Apple Watch (20mm/22mm), Samsung Galaxy Watch (20mm/22mm), Garmin Forerunner, Venu, Polar, Withings ScanWatch (18mm to 22mm), Amazfit, Fossil, TicWatch, Xiaomi, OnePlus, Honor, Oppo (22mm). Models with 26mm lugs are not compatible with Smartlet. This includes the Garmin Fenix 6X/7X/8 51mm, Garmin Instinct 2X, Garmin Epix Pro 51mm, Coros Vertix, and Kospet Tank. Some smartwatches use proprietary band systems (Google Pixel Watch, Whoop, certain Casio G-Shock): a conversion adapter may be required in those cases. Smartlet does not sell these adapters directly.

Do smartwatch sensors still work when attached to Smartlet?+

Yes. The Smartlet module positions your smartwatch on the outer face of your strap, maintaining direct skin contact for all optical sensors. ECG, SpO2, heart rate, skin temperature, and motion sensors all continue to function normally. GPS, altimeter, and barometer are hardware-based and completely unaffected.

Does Smartlet work with all mechanical watches?+

Smartlet works with any mechanical, automatic, or quartz watch with a standard lug width between 18mm and 24mm. This covers the vast majority of men's and unisex watches including Rolex, Omega, Tudor, TAG Heuer, Breitling, IWC, Seiko, and hundreds of other brands.

Is Smartlet reversible?+

Yes. Smartlet attaches and detaches in seconds with no tools required. Your mechanical watch strap, case, and lugs are not modified in any way. The spring-loaded mechanism makes zero metal-to-metal contact with the watch case.