| Number | Name | Date | Kind |
|---|---|---|---|
| D238148 | Dilot | Dec 1975 | |
| D302774 | Murphy | Aug 1989 | |
| D338312 | Licari | Aug 1993 | |
| 3419184 | Asenbauer | Dec 1968 | |
| 3448888 | Smith et al. | Jun 1969 | |
| 4819795 | Swaney | Apr 1989 |
| Entry |
|---|
| Material Flow Inc. 1991, p. 126 as shown. |
| Rubbermaid Cat 1985, p. 12, Bottom Right of the Page. |