| duct opening size | outside dimensions |
| 2.25 by 10 inches (3 inches wide overall) |
2.875 by 11.375 |
| 2.25 by 14 inches (3 inches wide overall) |
2.875 by 15.375 |
| 4 by 10 inches | 5.75 by 11.75 |
| 4 by 12 inches | 5.875 by 13.875 |
| 4 by 14 inches | 6 by 16 |
| 4 by 8 inches | 5.875 by 9.75 |
| 6 by 10 inches | 7.875 by 11.875 |
| 6 by 12 inches | 7.875 by 13.875 |
| 6 by 14 inches | 8 by 15.875 |
| 6 by 6 inches | 7.25 by 7.25 |
| 8 by 12 inches | 10 by 13.875 |
| 8 by 14 inches | 10 by 16.125 |
| 8 by 8 inches | 9 by 9 |
| 10 by 10 inches | 11.25 by 11.25 |
| 10 by 14 inches | 11.875 by 16 |
| 12 by 12 inches | 13.75 by 13.75 |
| 14 by 14 inches | 15.875 by 15.875 |
| 14 by 24 inches | 15.75 by 25.875 |
| 14 by 30 inches | 16.25 by 31.875 |
| 20 by 30 inches | 22 by 31.75 |
| 24 by 24 inches |
note: all opera grilles have a ridge on the back unless they are for 2.25 inch width duct openings or the 20 by 25 inch, in which case they are flat. return to home page