Description

Inspired by the iconic Daydate design, and featuring the prestigious Automatic Miyota Calibre, we present the Seikojust day-date mod. A 39 mm high-end quality watch combining the perfect alliance between excellence and accessibility.

Carefully assembled by experts with the next features:

  • Diameter: 39mm (excluding the crown)
  • Movement: Automatic Miyota Calibre 
  • Thickness: 12mm
  • Glass: Sapphire, anti-scratch with anti-reflective treatment
  • Luminova: Yes
  • Case: 316L stainless steel
  • Crown: Screwed
  • Wrist size: 14,5cm to 22cm (adjustable)
  • Lugs: 20mm
  • Bracelet: 316L stainless steel (with a security clasp)
  • Water resistance: 3 ATM
  • Day-Date: Fully functioning day and date 

Disclaimer:
This is a custom-built timepiece using genuine Seiko components, such as the movement. It is a third-party modification and is not affiliated with, endorsed by, or manufactured by Seiko Watch Corporation. “Seiko” is mentioned only to describe the origin of certain parts used in this custom build. All trademarks are the property of their respective owners.


Shipping & Returns

Free tracked shipping is available to the destinations shown at checkout. Each made-to-order watch takes 2–3 business days to build and test, followed by 7–10 business days in transit after dispatch. Watches may be returned within 14 days of delivery if unused and in original condition with packaging; we cover return shipping.


Can I service my watch locally?

Yes. Any competent local watchmaker can service your watch. We use genuine, dependable Seiko automatic calibres renowned for their durability, so maintenance is rarely required under normal wear.


What is an automatic watch?

An automatic watch has no battery. The movement of your wrist winds its mechanical movement while you wear it. If left unworn for around 42 hours it may stop; simply wear it again or gently turn the crown to restart it. This traditional watchmaking mechanism is more intricate than quartz.


What makes our watches high quality?

Every watch is built with a genuine Seiko automatic movement, scratch-resistant sapphire crystal and corrosion-resistant 316L stainless steel. Each piece is assembled, regulated and inspected before dispatch.


Description

Inspired by the iconic Daydate design, and featuring the prestigious Automatic Miyota Calibre, we present the Seikojust day-date mod. A 39 mm high-end quality watch combining the perfect alliance between excellence and accessibility.

Carefully assembled by experts with the next features:

  • Diameter: 39mm (excluding the crown)
  • Movement: Automatic Miyota Calibre 
  • Thickness: 12mm
  • Glass: Sapphire, anti-scratch with anti-reflective treatment
  • Luminova: Yes
  • Case: 316L stainless steel
  • Crown: Screwed
  • Wrist size: 14,5cm to 22cm (adjustable)
  • Lugs: 20mm
  • Bracelet: 316L stainless steel (with a security clasp)
  • Water resistance: 3 ATM
  • Day-Date: Fully functioning day and date 

Disclaimer:
This is a custom-built timepiece using genuine Seiko components, such as the movement. It is a third-party modification and is not affiliated with, endorsed by, or manufactured by Seiko Watch Corporation. “Seiko” is mentioned only to describe the origin of certain parts used in this custom build. All trademarks are the property of their respective owners.


Shipping & Returns

Free tracked shipping is available to the destinations shown at checkout. Each made-to-order watch takes 2–3 business days to build and test, followed by 7–10 business days in transit after dispatch. Watches may be returned within 14 days of delivery if unused and in original condition with packaging; we cover return shipping.


Can I service my watch locally?

Yes. Any competent local watchmaker can service your watch. We use genuine, dependable Seiko automatic calibres renowned for their durability, so maintenance is rarely required under normal wear.


What is an automatic watch?

An automatic watch has no battery. The movement of your wrist winds its mechanical movement while you wear it. If left unworn for around 42 hours it may stop; simply wear it again or gently turn the crown to restart it. This traditional watchmaking mechanism is more intricate than quartz.


What makes our watches high quality?

Every watch is built with a genuine Seiko automatic movement, scratch-resistant sapphire crystal and corrosion-resistant 316L stainless steel. Each piece is assembled, regulated and inspected before dispatch.

AFTER PURCHASE SUPPORT

Ongoing Servicing, support and spare parts whenever you need them.

Servicing & Regulation

Cleaning, regulation and maintenance to keep your watch performing accurately.

Ongoing Support

Friendly aftercare and expert guidance whenever you need it.

2 Year Warranty

Every watch is protected by our comprehensive two-year warranty.

Spare Parts & Replacements

Replacement links, straps and essential parts are available when required.

The Mod LABS

TRUSTED BY WATCH LOVERS WORLD WIDE

4.7 / 5   ★★★★★ – Loved by over 800 watch lovers

What you Actually Receive

Engineered for Daily Wear

Designed to feel comfortable, reliable and effortless every day.

High Calibre Genuine Seiko Movements

Proven automatic movements delivering dependable, precise mechanical performance.

Functional by Design

From rotating bezels and hacking seconds to GMT functionality, every feature is made to work as intended.

High-grade 316L Stainless Steel

Built for durability, corrosion resistance and a premium finish.

Hand Built to Your Order

Individually assembled by hand with care and attention to detail.

Ultra Durable Sapphire Crystal

Highly scratch resistant for lasting clarity and everyday protection.

Made for Every Moment

From the morning commute to late-night drives, every watch from The Mod Labs is designed to complement your everyday. Built with premium materials, timeless design and reliable performance, it’s a watch made to be worn—not kept in a box.

Q&A’s

Please read our Q&A’s page for more information.

What is a Seiko Mod?

A Seiko mod is a custom-built watch assembled with aftermarket components around a Seiko movement. Each product page lists its movement and specifications. The Mod Labs is independent and is not affiliated with Seiko Watch Corporation.

How Can I Adjust the Size of my Watch?

A complimentary bracelet-adjustment tool kit is included with every watch order. You can use it to resize your bracelet at home or ask a local watchmaker to help. Contact us if you need assistance.

Is it Possible to Customize my Watch?

The online design-your-own watch builder is coming soon. For now, choose the options shown on each product page. If you want a different dial or strap, contact us before ordering to check what can be supplied.

Do you use Authentic Seiko movements?

Yes. Our watches use genuine Seiko movements. The calibre varies by model; check the product page for its movement, such as an NH-series automatic calibre or VK63 meca-quartz movement.

Can I Order a Watch Without the Seiko Logo?

Some dials can be supplied without the Seiko logo. Availability depends on the model and parts in stock, so please contact us before ordering to confirm the option for your chosen watch.

What are the Production and Delivery Times?

Each watch is made to order. Please allow 2–3 business days for production, testing and preparation before dispatch. Tracked worldwide delivery is estimated at 7–10 business days after dispatch. Courier and customs delays may affect delivery times.