Elevate your timepiece with the Genuine Miyota 8285 Automatic Mechanical Movement Mod Day-Date Watch Mechanism. Renowned for its precision and reliability, this 21‑jewel movement delivers flawless day‑date functionality with week indicators positioned at 12:00 and date markers at 3:00. Whether you’re a seasoned watchmaker or a DIY enthusiast, this mechanism is engineered for seamless integration and long‑lasting performance.
Key Highlights
- Authentic Miyota 8285 movement – trusted by professionals worldwide
- 21 high‑quality jewels for reduced friction and enhanced durability
- Day‑date display with week indicator at 12:00 and date at 3:00 for intuitive time reading
- Automatic (self‑winding) power source – no battery replacements needed
- Compact 28 mm diameter, perfect for mid‑size cases
- Precision 10‑Hz frequency, ensuring accurate timekeeping
- Corrosion‑resistant brass case and stainless steel components
- Compatible with a wide range of watch cases and calibers
Technical Specifications
- Movement type: Automatic Mechanical
- Caliber: Miyota 8285 Mod Day-Date
- Jewels: 21
- Frequency: 10 Hz (10 000 vibrations per hour)
- Power reserve: ~40 hours (typical)
- Case diameter: 28 mm
- Case thickness: 7.5 mm
- Spring bar length: 24 mm
- Materials: Brass, stainless steel, silicon escapement
Why Choose the Miyota 8285?
With a heritage of over 50 years in precision watchmaking, Miyota consistently delivers movements that combine reliability with affordability. The 8285 Mod Day-Date is engineered for:
- Consistent performance in diverse environments
- Easy assembly and maintenance for watchmakers
- High resale value for collectors and custom watch builders
- Compatibility with a broad range of case sizes and designs
Compatibility & Installation
Designed for mid‑size watch cases, the Miyota 8285 fits most 28 mm to 30 mm dial configurations. Its standard 24 mm spring bar and 7.5 mm case thickness make it a versatile choice for:
- Custom watch projects
- Refurbishment of vintage timepieces
- Professional watch repair shops
- DIY watch enthusiasts looking for a reliable base movement
Warranty & Support
We offer a 12‑month manufacturer’s warranty covering defects in materials and workmanship. For any installation queries or technical support, our dedicated team is available via email or phone. Experience the confidence of a guaranteed, high‑performance movement that stands the test of time.
Price: Original price was: $ 98.11.$ 48.08Current price is: $ 48.08.

