| Number | Name | Date | Kind |
|---|---|---|---|
| 1202428 | Rennell | Oct 1916 | |
| 1318145 | Harbaugh | Oct 1919 | |
| 1423523 | Grow | Jul 1922 | |
| 3486757 | Loescher | Dec 1969 |
| Number | Date | Country |
|---|---|---|
| 828,601 | Jan 1952 | DEX |
| 643925 | Sep 1950 | GBX |
| 817598 | Aug 1959 | GBX |
| Entry |
|---|
| Booklet, "Schweiger Design"--Record & Tape Cleaning Products--1974/75, pp. 7 & 8. |