Benge Instrument Serial Numbers
| Serial Number | Date |
| Up to 10,000 | Before 1973 |
| 10000 | 1973 |
| 12000 | 1974 |
| 14000 | 1975 |
| 18000 | 1976 |
| 21000 | 1977 |
| 26000 | 1978 |
| 30000 | 1979 |
| 34000 | 1981 |
- Legendary
- People.
- Legendary
- Brands.
| Serial Number | Date |
| Up to 10,000 | Before 1973 |
| 10000 | 1973 |
| 12000 | 1974 |
| 14000 | 1975 |
| 18000 | 1976 |
| 21000 | 1977 |
| 26000 | 1978 |
| 30000 | 1979 |
| 34000 | 1981 |