| Number | Name | Date | Kind |
|---|---|---|---|
| 738712 | Cole | Sep 1903 | |
| 1228836 | Schulse | Jun 1917 | |
| 1368703 | Czerny | Feb 1921 | |
| 1398348 | Weber | Nov 1921 | |
| 1823379 | Schmidt | Sep 1931 | |
| 1834672 | Austin | Dec 1931 | |
| 2020884 | Garcia | Nov 1935 | |
| 3031860 | Middleton | May 1962 | |
| 3052377 | Bill | Sep 1962 | |
| 3327485 | Ter Bush | Jun 1977 | |
| 3363432 | Sholtes | Jan 1968 | |
| 3365904 | Ross | Jan 1968 | |
| 3367133 | Dreis et al. | Feb 1968 | |
| 3468370 | Castillo | Sep 1969 | |
| 3495612 | Moreland, II | Feb 1970 | |
| 3541808 | Materese | Nov 1970 | |
| 3572553 | Ogden | Mar 1971 | |
| 3688950 | Parish | Sep 1972 | |
| 3731845 | Booth | May 1973 | |
| 3824801 | Laudato, Jr. | Jul 1974 | |
| 3845884 | Hall et al. | Nov 1974 | |
| 3921855 | Syverson | Nov 1975 | |
| 4575615 | Shigenobu et al. | Mar 1986 | |
| 4597509 | Pereira | Jul 1986 | |
| 4649809 | Kanezashi | Mar 1987 | |
| 4699188 | Baker et al. | Oct 1987 | |
| 4728005 | Jacobs et al. | Mar 1988 | |
| 4757921 | Snowball | Jul 1988 | |
| 4779426 | Desrosiers | Oct 1988 | |
| 4792059 | Kerner et al. | Dec 1988 | |
| 4801375 | Padilla | Jan 1989 | |
| 4808346 | Strenger | Feb 1989 | |
| 4834267 | Schroer et al. | May 1989 | |
| 4881661 | Jones | Nov 1989 | |
| 4923091 | Sutera | May 1990 | |
| 4958747 | Sheets | Sep 1990 |
| Number | Date | Country |
|---|---|---|
| 564565 | Mar 1931 | DE2 |
| 95247 | Mar 1921 | CHX |
| 236688 | Jul 1925 | GBX |
| Entry |
|---|
| Water Conditioning & Purification; Buyer's Guide (Apr., 1989) p. 45 Advertisement. |