Baseplates, plates for additional mechanisms (modules) and bridges must have:
- Polished chamfers.
- Straight-grained sides.
- Circular-graining or finishes that eliminate all machining traces.
- Smoothed-down bridge supports.
- Polished bevels in holes and recesses.
- Polished sinks for jewel holes.
The tops of bridges must be finished with Geneva stripes or any other decoration that eliminates machining marks.