1. Must be 18 or 16 size.
2. Have a minimum of 17 jewels.
3. Be adjusted to 5 positions. (a sixth was added later.)
4. Keep time plus or minus 30 seconds per week.
5. Be adjusted to temperature 40 to 95 degrees F.
6. Must have a double roller.
7. Must be lever set.
8. Winding stem at 12 o'clock.
9. Must have a plain Arabic dial with heavy hands. |
