| Number | Name | Date | Kind |
|---|---|---|---|
| D256581 | Bartin | Aug 1980 | |
| D297231 | Rasnake et al. | Aug 1988 | |
| D298313 | De Jong | Nov 1988 | |
| 2857570 | Simpson | Oct 1958 | |
| 4611875 | Clarke et al. | Sep 1986 | |
| 4648682 | Tubbs | Mar 1987 | |
| 4878848 | Ingalsbe | Nov 1989 | |
| 4975087 | Williams et al. | Dec 1990 |
| Number | Date | Country |
|---|---|---|
| 2617662 | Jan 1989 | FRX |
| Entry |
|---|
| Telephone Line TesterITC-3007 on p.V of Specialized Products Co. Fall 1989 Catalog. |
| Connectors and cables B on p. 69 of Specialized Products Co. Fall 1989 Catalog. |