| Number | Name | Date | Kind |
|---|---|---|---|
| 2515894 | Polk | Jul 1950 | |
| 3165390 | Parken et al. | Jan 1965 | |
| 3237386 | Farr et al. | Mar 1966 | |
| 3483676 | Sargisson | Dec 1969 | |
| 3520114 | Pall et al. | Jul 1970 | |
| 3713280 | Keller et al. | Jan 1973 | |
| 3915679 | Roach et al. | Oct 1975 |
| Entry |
|---|
| STB Strata Engine Air Systems, Donaldson Company, Inc., Bulletin 1200-1240, Copyright 1974. |
| Strata Panel Inertial Separators, Donaldson Company, Inc., Bulletin 3000-3020, Copyright 1974. |