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Satisfaction Guaranteed or Your Money Back
2-Year Warranty for Peace of Mind
Free Bracelet Adjustment Tools Included
Glass: Sapphire, Anti-reflective coating
Dial: Nautilus
Hands: Nautilus
Case: Nautilus 41 mm
Thickness: 12 mm
Case back: Sapphire glass
Bracelet: Nautilus 25 mm
Bracelet length: Custom size
Water resistance: 100 m
MOVEMENT
Mouvement : Seiko NH38a Automatic Mechanical
Fonctions :
- Automatic winding
- Hacking seconds
Power Reserve: 41 hours on full charge
Jewels: 24
TECHNICAL INSPECTIONS
- Water Resistance
- Demagnetization
- Chronometer Calibration (-5s/+5s per day)
All tests are thoroughly completed to guarantee your satisfaction!
SHIPPING
Risk-Free Guarantee
If you’re not satisfied with your watch, you can return it within 30 days. This guarantee starts from the moment your package is delivered.
It takes 3 to 5 business days to assemble and test your watch, ensuring optimal performance.
Shipping
Once assembled, your watch will be shipped, which typically takes 10 to 15 business days.
Overall Timeline
The entire process, from assembly to delivery, takes approximately 13 to 20 business days (Monday to Friday). This ensures every watch meets our high standards before reaching you.
Cost
Shipping is completely free.
Enjoy a worry-free experience with guaranteed quality and service!
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WINTER SALE
Treat yourself to elegance this winter with €50 off!
Use code: WINTER50
Need help?
FREQUENTLY ASKED QUESTIONS
A Seiko mod is a one-of-a-kind timepiece, custom-made and impossible to find in traditional retail stores.
Handcrafted by experts, these watches combine original Seiko components with carefully selected non-Seiko parts, chosen for their quality and style.
Please note that these are not official Seiko products. Our company is entirely independent and has no affiliation with Seiko or any other brand.
We use NH35, NH70, and NH72 automatic mechanical movements for our modified Seiko watches. These movements, manufactured by Seiko, are renowned for their reliability and accuracy, providing an exceptional watchmaking experience for our customers. Each of these movements is carefully selected to ensure long-lasting performance and outstanding quality, adding invaluable value to our modified Seiko watches.
Each watch undergoes a series of rigorous tests to ensure its performance and reliability:
- Water Resistance: A thorough check of the water resistance to ensure perfect sealing.
- Demagnetization: A demagnetization process to preserve the proper functioning of sensitive components.
- Chronometer Adjustment: Precise adjustment of the watch to achieve accuracy within -5 to +5 seconds per day.
These quality checks are carried out with care before shipping, ensuring you receive a watch that is ready to use, reliable, and high-performing.
For every order, we provide you with the necessary tool to adjust the bracelet to your wrist yourself.
This allows you to easily customize the fit at home, at no extra cost.
Delivery of In-Stock Watches
- Shipping within 48 business hours.
Delivery of Made-to-Order Watches
- Assembly: 10 to 15 business days.
- Shipping within 48 hours.
Accessory Delivery
- Shipping within 48 business hours.
Tracking and Shipping Fees
- Tracking number provided upon shipment.
- Shipping fees vary based on weight and destination.
Returns and Exchanges
- Please refer to our Return Policy.

Create a unique watch, combining style and precision.
Create the watch of your dreams
At Chrono Mod, customize every detail of your watch, from the dial to the strap. Each piece is assembled on a high-quality Seiko movement, ensuring reliability and precision for a truly personalized result.
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