|
| US4227190 | 26. Febr. 1979 | 7. Okt. 1980 | | Water alarm for monitoring floor moisture |
| US4255747 | 15. Nov. 1978 | 10. März 1981 | | Sump pump level warning device |
| US4369438 | 13. Mai 1980 | 18. Jan. 1983 | | Sump pump detection and alarm system |
| US4849739 | 30. Juni 1988 | 18. Juli 1989 | Ala Inc., a New Jersey Corporation | Liquid detector for air pressure type fire sprinkler system |
| US5006834 | 15. März 1989 | 9. Apr. 1991 | | Liquid level alarm |
