Does Smartlet work with the Seiko 5?

Yes for 109 of the 138 Seiko 5 Sports references in our base, on 18mm to 22mm lugs with standard spring bars. Some versions use a fitting Smartlet One cannot take, so check your exact reference in the table before you order.

Which Seiko 5 references are compatible with Smartlet?

109 of the 138 Seiko 5 Sports references in our base fit Smartlet One, on 18mm to 22mm lugs with standard spring bars. Some versions use a fitting Smartlet One cannot take, so check your exact reference in the table before you order.

Can I wear an Apple Watch with my Seiko 5?

Yes. The watch adapters seat in the Seiko 5's lug holes in place of the spring bars, and Smartlet holds your smartwatch on the same wrist at the same time.

Where can I buy Smartlet for the Seiko 5?

Smartlet is available at smartlet.io in Classic, Shadow, and Titanium. All finishes are compatible with Seiko 5 references at 19mm to 22mm lug widths.

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.

Wear a smartwatch with your Seiko Seiko 5

Smartlet is compatible with the Seiko Seiko 5. Lug width: 19mm / 20mm / 22mm, supported with watch adapters in the matching width. The watch adapters seat in the lug holes in place of the spring bars. No modification to the watch required. Fully reversible.

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Seiko Seiko 5 compatibility

Wear a smartwatch with your Seiko Seiko 5

In short Smartlet is compatible with the Seiko Seiko 5. Lug width: 19mm / 20mm / 22mm, supported with watch adapters in the matching width. The watch adapters seat in the lug holes in place of the spring bars. No modification to the watch required. Fully reversible.

The Seiko 5 is the watch that proved automatic movements could reach everyone. Launched in 1963 with five principles - automatic winding, day/date display, water resistance, recessed crown at 4 o'clock, and a durable case - the 5 series has remained in continuous production for over sixty years. The current Sport line modernised the design language in 2020, adding dial colours and case proportions that the watch community received as genuinely good design. More Seiko 5s are sold annually than most Swiss brands produce in a decade.

Wear yours How it works

The problem

Choosing between health data and horological heritage every morning.

The solution

Smartlet One replaces your Seiko Seiko 5 strap: the watch adapters seat in the lug holes in place of the spring bars, and your smartwatch sits on the same wrist. Both watches run at the same time, with no modification to the watch, and the change is fully reversible.

Model

Seiko Seiko 5

Lug width

18mm / 20mm / 22mm

References

110 covered

Reversible

Fully

Choose your Smartlet

Compatibility

Seiko Seiko 5 models supported

Covered references

110 references covered.

ReferenceMaterialDialLugSmartlet

SRPD55Steel 42.5mmBlack22mmCompatible

SRPD51Steel 42.5mmBlue22mmCompatible

SRPD53Steel 42.5mmPepsi22mmCompatible

SRPD65K142.5mm22mmCompatible

SRPD79K142.5mm22mmCompatible

SSK001K142.5mm22mmCompatible

SSK003K142.5mm22mmCompatible

SRPD63K142.522mmCompatible

SSK005K142.522mmCompatible

SSK023K1Stainless steel 39.4mmBlack20mmCompatible

SRPD51K1Stainless steel 42.5mmBlue22mmCompatible

HDB004K1Stainless steel 42.5mmWhite22mmCompatible

HDB005K1Stainless steel 42.5mmGreen22mmCompatible

SBSA098Stainless steel 42.5mmBlue22mmCompatible

SBSA099Stainless steel 42.5mmBlue22mmCompatible

SBSA111Stainless steel 39.4mmBlack20mmCompatible

SBSA113Stainless steel 39.4mmBlue20mmCompatible

SBSA115Stainless steel 39.4mmGrey20mmCompatible

SBSA117Stainless steel 39.4mmGrey20mmCompatible

SBSA119Stainless steel 39.4mmBlue20mmCompatible

SBSA121Stainless steel 39.4mmBlack20mmCompatible

SBSA135Stainless steel 42.5mmSilver20mmCompatible

SBSA139Stainless steel 39.4mmBlack20mmCompatible

SRP425K1Stainless steel 44mmBlue22mmCompatible

SRP427K1Stainless steel 44mmBlack22mmCompatible

SRP557K1Stainless steel 44mmBlack22mmCompatible

SRPG41K1Stainless steel 39.4mmBrown20mmCompatible

SRPJ81K1Stainless steel 36mmBlack18mmCompatible

SRPJ83K1Stainless steel 36mmBeige18mmCompatible

SRPJ85K1Stainless steel 36mmBlack18mmCompatible

SRPJ87K1Stainless steel 36mmBeige18mmCompatible

SRPK02K1Stainless steel 42.5mmBlue22mmCompatible

SRPK87K1Stainless steel 37mmDark blue18mmCompatible

SRPK89K1Stainless steel 37mmBlack18mmCompatible

SRPK91K1Stainless steel 37mmBeige18mmCompatible

SRPK97K1Stainless steel 42mmBlue22mmCompatible

SRPK99K1Stainless steel 42mmBlack22mmCompatible

SRPL55K1Stainless steel 37.4mmBlue18mmCompatible

SRPL57K1Stainless steel 37.4mmGreen18mmCompatible

SRPL59K1Stainless steel 37.4mmGold18mmCompatible

SRPL79K1Stainless steel 38mmBlack20mmCompatible

SSA335J1Stainless steel 44mmGrey22mmCompatible

SSK033K1Stainless steel 42mmSilver22mmCompatible

SSK035K1Stainless steel 42mmGreen22mmCompatible

SSK036K1Stainless steel 42mmBlack22mmCompatible

SSK019J8Stainless steel 42.5mm22mmCompatible

SSK047Stainless steel (hard coating) 42.5mm22mmCompatible

HDB007Stainless steel 41mmWhite20mmCompatible

SSK059Stainless steel 39.4mm20mmCompatible

SSK021J8Stainless steel 42.5mm22mmCompatible

HDB006Stainless steel 41mm20mmCompatible

HDB008Stainless steel 41mm20mmCompatible

HDB001Stainless steel 39.4mm20mmCompatible

HDB002Stainless steel 39.4mm20mmCompatible

SSK025Stainless steel (hard coating) 39.4mm20mmCompatible

HDB009Stainless steel 41mm20mmCompatible

SBSA125J22mmCompatible

SNZG09J1Stainless steel 42mmGreen22mmCompatible

SNZG1522mmCompatible

SRPD55K3Stainless steel 42.5mmBlack22mmCompatible

SRPD65K3Stainless steel 42.5mmBlack22mmCompatible

SRPD65K4Stainless steel 42.5mmBlack22mmCompatible

SRPE63Stainless steel 40mm20mmCompatible

SRPE69Stainless steel (hard coating) 40mm20mmCompatible

SRPE79Stainless steel (hard coating) 42.5mm22mmCompatible

SRPF19Stainless steel 42.5mm22mmCompatible

SRPF69Stainless steel 42.5mm22mmCompatible

SRPF71Stainless steel (hard coating) 42.5mm22mmCompatible

SRPF73Stainless steel (hard coating) 42.5mm22mmCompatible

SRPF75Stainless steel (hard coating) 42.5mm22mmCompatible

SRPG4220mmCompatible

SRPG61Stainless steel 42.5mm22mmCompatible

SRPH21Stainless steel 39.4mm20mmCompatible

SRPH23Stainless steel 39.4mm20mmCompatible

SRPH25Stainless steel (hard coating) 39.4mm20mmCompatible

SRPH31Stainless steel 39.4mm20mmCompatible

SRPH81J8Stainless steel 39.4mmBeige20mmCompatible

SRPJ49Stainless steel 42.5mm22mmCompatible

SRPJ75Stainless steel (hard coating) 42.5mm22mmCompatible

SRPJ79Stainless steel 42.5mm22mmCompatible

SRPJ89Stainless steel 36.4mm18mmCompatible

SRPK03Stainless steel 42.5mm22mmCompatible

SRPK05Stainless steel 42.5mm22mmCompatible

SRPK07Stainless steel 42.5mm22mmCompatible

SRPK13Stainless steel 42.5mm22mmCompatible

SRPK1739.5mm20mmCompatible

SRPK17K1Stainless steel 39.5mmBlack20mmCompatible

SRPK18J8Stainless steel 42.5mm22mmCompatible

SRPK22J8Stainless steel 42.5mm22mmCompatible

SRPL05Stainless steel 38.5mm20mmCompatible

SRPL33Stainless steel 42.5mm22mmCompatible

SRPL35Stainless steel 42.5mm22mmCompatible

SRPL91Stainless steel 38.2mm20mmCompatible

SRPL93Stainless steel 38.2mm20mmCompatible

SRPL95Stainless steel 42.5mm22mmCompatible

SRPM09Stainless steel 39.4mm20mmCompatible

SSK017JTStainless steel 42.5mmYellow22mmCompatible

HDB003Stainless steel 42.5mm22mmCompatible

HDB004Stainless steel 42.5mm22mmCompatible

HDB005Stainless steel 42.5mm22mmCompatible

SBSA19936.4mmNatural/Cream18mmCompatible

SBSC020Stainless steel22mmCompatible

SSK001Stainless steel 42.5mmBlack22mmCompatible

SSK003Stainless steel 42.5mm22mmCompatible

SSK005Stainless steel 42.5mm22mmCompatible

SSK023Stainless steel 39.4mmBlack20mmCompatible

SSK033Stainless steel 42.5mmWhite22mmCompatible

SSK035Stainless steel 42.5mm22mmCompatible

SSK036Stainless steel 42.5mm22mmCompatible

SNZ32737.5mmBlue/Navy20mmCompatible

Seiko Seiko 5 lug widths: 18mm / 20mm / 22mm

Frequently paired

Smartwatches worn with Seiko Seiko 5

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

Watch 4 to 9 - Classic - FE - Ultra - Ultra2

Combination guides

Wear it both ways

Seiko Seiko 5 + Fitbit

Fitbit

→

Also compatible

Other brands

Other iconic models in the Smartlet compatibility library.

Longines Master Collection

Blancpain Villeret

View all models

Watch brand compatibility guide

Step by step

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

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

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

Questions

Frequently asked questions

Does Smartlet work with the Seiko 5?

Yes for 109 of the 138 Seiko 5 Sports references in our base, on 18mm to 22mm lugs with standard spring bars. Some versions use a fitting Smartlet One cannot take, so check your exact reference in the table before you order.
Which Seiko 5 references are compatible with Smartlet?

109 of the 138 Seiko 5 Sports references in our base fit Smartlet One, on 18mm to 22mm lugs with standard spring bars. Some versions use a fitting Smartlet One cannot take, so check your exact reference in the table before you order.
Can I wear an Apple Watch with my Seiko 5?

Yes. The watch adapters seat in the Seiko 5's lug holes in place of the spring bars, and Smartlet holds your smartwatch on the same wrist at the same time.
Where can I buy Smartlet for the Seiko 5?

Smartlet is available at smartlet.io in Classic, Shadow, and Titanium. All finishes are compatible with Seiko 5 references at 19mm to 22mm lug widths.
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.

Join the movement

Wear a smartwatch with your Seiko Seiko 5

Wear a smartwatch with your Seiko Seiko 5

Choose your Smartlet

Seiko Seiko 5 models supported

Covered references

Smartwatches worn with Seiko Seiko 5

Wear it both ways

Other brands

Step by step

Replace your strap

Connect your wearable

Wear both simultaneously

Frequently asked questions