| Number | Name | Date | Kind |
|---|---|---|---|
| 2422534 | DuBois | Jun 1947 | |
| 2527027 | Mull | Oct 1950 | |
| 2877463 | Watkins | Mar 1959 | |
| 3000011 | Sterne et al. | Sep 1961 | |
| 3027562 | Widenor | Apr 1962 | |
| 3395406 | Smith | Aug 1968 | |
| 3418658 | Danico | Dec 1968 | |
| 3517393 | Beauchef | Jun 1970 | |
| 4264988 | Specht | May 1981 | |
| 4468819 | Ohno et al. | Sep 1984 | |
| 4670914 | Harris | Jun 1987 | |
| 4689838 | Angermann et al. | Sep 1987 | |
| 4716601 | McNeal | Jan 1988 |
| Number | Date | Country |
|---|---|---|
| 0699465 | Nov 1953 | GBX |
| 0879077 | Oct 1961 | GBX |
| 0921203 | Mar 1963 | GBX |
| 0931850 | Jul 1963 | GBX |
| Entry |
|---|
| American Optical Safety Products Brochure (2 Sides); 1976. |