OP XXXI
hours, minutes, small seconds, GMT
178 components,
COSC Certified,
looks similar like the OP XXX,
It is unclear which basis the movement has, properties fits perfect to a Valjoux 7750 caliber, but the OP XXXI has like the OP XXX a balance bridge and not like all 7750s a balance cock!
On the base plate is the engraving “MVB” visible, that is typical naming for caliber from Richmont group. Because of that we tend to ValFleurier as producer.
| Label | Value |
|---|---|
| Model | OP XXXI |
| Winding | Automatic |
| Basis | Valjoux 7750 or ValFleurier? |
| Producer | Horlogère ValFleurier? |
| Introduction | 2017 |
| Dimension | 29,89 mm (13 1/4''') |
| Frequency | 28.800 vph (4 Hz) |
| Power Reserve | 50 h |
| Jewels | 25 |
| Height | 7,90 mm |