Seiko NH05
🛠️ Basic Specifications:
- Manufacturer: SII (Seiko Instruments Inc.), Japan
- Caliber: NH05A
- Type: Automatic movement with manual winding and hacking seconds
- Movement type: Mechanical automatic
📏 Dimensions:
- Diameter: Approx. 23.3 mm (10½ lignes)
- Height: Approx. 5.1 mm
- Dial feet positions: Typically at 0° and 180°
⚙️ Technical Details:
- Jewels: 24
- Beat rate: 21,600 vibrations per hour (6 beats per second / 3 Hz)
- Power reserve: Approximately 40 hours
- Winding direction: Bidirectional (Magic Lever system)
- Manual winding: Yes
- Hacking (stop seconds): Yes
⏱️ Functions:
- Display: Hour / Minute / Central seconds
- Hand bore diameters:
-
- Hour: 1.50 mm
- Minute: 0.90 mm
- Seconds: 0.20 mm
-
📈 Accuracy (factory specs):
- Daily rate: −20 to +40 seconds/day
(Regulatable to tighter tolerances by a watchmaker)
⚒️ Compatibility / Use Cases:
- Designed for: Smaller watches (women’s or compact men’s watches)
- Case fitting: Compatible with compact or slim case designs
- Popular for: Entry-level automatic watches with small case sizes
