Historical Archive of American Horology & Vintage Timepieces
Illinois 438 Movement Specifications, Beat Rate & Dimensions
Original Horological Blueprint • Illinois Watch Company Illinois 438 Architecture
Technical Caliber Datasheet
| Manufacturer | Illinois |
| Caliber Reference | Illinois 438 |
| Movement Type | Manual |
| Diameter (Lignes) | — |
| Diameter (mm) | 39.75 mm |
| Height / Thickness | 3.9 mm |
| Jewel Count | 19 Jewels |
| Beat Rate / Frequency | 18,000 BPH |
| Lift Angle | 51° |
| Power Reserve | 38 hours |
| Escapement | Swiss Lever |
| Production Period | 1918 |
Historical Reference & Restoration Notes
The Illinois 438 is a celebrated example of vintage precision engineering. Featuring 19 jewels and operating at 18,000 BPH, surviving examples are prized by collectors and restorers.
Restoration enquiries:
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