| Number | Name | Date | Kind |
|---|---|---|---|
| D257810 | Wilson | Jan 1981 | |
| 1803084 | Wiziarde et al. | Apr 1931 | |
| 2665869 | Samuels | Jan 1954 | |
| 2937652 | Zimmer | May 1960 | |
| 3123850 | Piken | Mar 1964 | |
| 4287701 | Washington | Sep 1981 | |
| 4397438 | Chapman | Aug 1983 |
| Entry |
|---|
| Photograph of S-shaped clip; prior to 4/83. |