| Number | Date | Country | Kind |
|---|---|---|---|
| 92 00520 | Feb 1992 | MXX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 676536 | Ferguson | Jun 1901 | |
| 1899826 | Rice | Feb 1933 | |
| 3746039 | Demi | Jul 1973 | |
| 4187872 | Freeman et al. | Feb 1980 | |
| 4823838 | Ferlin | Apr 1989 | |
| 4927747 | Nitta | May 1990 | |
| 4929176 | Nitta | May 1990 |
| Entry |
|---|
| Robertshaw Controls Co., "Flame Repeatability East as One-Two-Three," Proportional Flow Gas Valve, Model BP Catalog, cover page & pp. 8, 9, 14 (date unknown). |