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Wear a smartwatch with your Seiko 5 | Smartlet

Seiko compatibility guide

Wear a smartwatch
with your Seiko Seiko 5

Smartlet is compatible with the Seiko Seiko 5. Lug width: 19mm / 20mm / 22mm - natively supported with no adapter. Installation uses the standard spring-bar system. No modification to the watch required. Fully reversible in seconds.

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.

ModelSeiko Seiko 5

Lug width19mm / 20mm / 22mm

Case size38mm / 40mm / 42mm

MovementCal. 4R36 / 7S36

Water resistance100m

Introduced1963

Smartlet compatibleYes

References

Covered references

Reference	Smartlet	Lug width	Case	Case material	Dial
5126-6010	Compatible	19mm	38mm	Stainless Steel	Silver
6119-6050-Rally	Compatible	20mm	40mm	Stainless Steel	Black/Orange Rally
6139-8002	Compatible	19mm	38mm	Stainless Steel	Blue
Vintage-5-Lion-1974	Compatible	19mm	38mm	Stainless Steel	Silver
7009-876A	Compatible	19mm	38mm	Gold-Tone	Champagne
7009-600A-AR	Compatible	20mm	40mm	Stainless Steel	Arabic Black
SRPD55	Compatible	22mm	42mm	Stainless Steel	Black
SRPD51	Compatible	22mm	42mm	Stainless Steel	Blue
SRPD53	Compatible	22mm	42mm	Stainless Steel	Pepsi
SNKZ15	Compatible	22mm	42mm	Stainless Steel	Black/Red
SNKZ17	Compatible	22mm	42mm	Stainless Steel	Black/Blue

Smartlet compatibility

The Seiko 5 uses 19mm to 22mm lug widths depending on reference. Smartlet attaches via the standard spring-bar system. Zero contact with the watch case, lugs, or crystal. Fully reversible in seconds.

Compatible smartwatches

Smartwatches to pair with your Seiko Seiko 5

All smartwatches below can be worn simultaneously with your Seiko Seiko 5 via Smartlet.

View all compatible smartwatches →

Same brand

Other Seiko models

All Seiko models below are also compatible with Smartlet.

View all Seiko references →

Similar models from other brands

Watch lovers who own a Seiko Seiko 5 also pair Smartlet with these models.

Rado

Captain Cook

18mm / 20mm / 21mm / 22mm

View all compatible models →

Questions

Frequently asked

Does Smartlet work with the Seiko 5?+

Yes. All current Seiko 5 Sport references use 19mm to 22mm lugs - natively supported by Smartlet. No adapter required.

Which Seiko 5 references are compatible with Smartlet?+

SRPD51, SRPD53, SRPD55 Sport series at 22mm, and older 7009 and 6119 series at 19mm and 20mm - all within Smartlet's native range.

Can I wear an Apple Watch with my Seiko 5?+

Yes. Smartlet attaches to the Seiko 5 via the spring-bar slots and holds your Apple Watch, Garmin, or other smartwatch on the same wrist simultaneously.

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.