| Number | Name | Date | Kind |
|---|---|---|---|
| 4017076 | Bai | Apr 1977 | |
| 4248010 | Fox | Feb 1981 | |
| 4262911 | Opresik | Apr 1981 | |
| 4736955 | Pollock | Apr 1988 | |
| 4819947 | Mackey | Apr 1989 | |
| 4995617 | Lee | Feb 1991 | |
| 5067727 | Crompton | Nov 1991 | |
| 5080374 | Yu et al. | Jan 1992 | |
| 5085442 | Lee | Feb 1992 | |
| 5123655 | Rones | Jun 1992 |
| Entry |
|---|
| "Grip Disc", Griptoys, Inc. (undated-may or may not constitute prior art). |