| DOBRO | |||||||
| 1927-37 | |||||||
| #number | year | ||||||
| 800-1400 | 1929 | california made | |||||
| 1400-2000 | 1930 | ||||||
| 2000-2600 | 1931 | ||||||
| 2600-3200 | 1932 | ||||||
| 3200-3900 | 1933 | ||||||
| 4000's | 1933 | mostly regal made | |||||
| 5000-5600 | 1933 | california made | |||||
| 5700-7600 | 1934-1936 | california and regal made | |||||
| 8000-9000 | 1936-1937 | ||||||
| L9000 | 1937 | regal made | |||||
| A prefix | 1936 | ||||||
| B prefix | 1932-1933 | ||||||
| M prefix | ca.1935 | ||||||
| model "el monte" | 1962-1964 | ||||||
| model "gardena" | 1965-1966 | ||||||
| OMI MODELS | |||||||
| #number | year | ||||||
| 101-401 | 1967-1970 | ||||||
| 402-712 | 1971 | ||||||
| 713-1427 | 1972 | ||||||
| 1428-2296 | 1973 | ||||||
| 2297-2372 | 1974 | ||||||
| 1st numeral is last digit of year | 1974-1979 | ||||||
| numeral before last letter is last digit of year,1st numeral is decade | 1980-1988 | ||||||
| 2 numerals before last letter are last 2 digits of year | 1988-1994 | ||||||
| 2 final numerals are last 2 digits of year | 1995-1997 | ||||||
| 1st numeral is last digit of year,last numeral is decade | 1998- | ||||||