ATCM-Pyramid Spindle
| Model | INSIDE CURB | ACRYLIC | |
| INCHES | MM | ||
| 2020 | 14.5 x 14.5 | 368 x 368 | ✓ |
| 2828 | 22.5 x 22.5 | 572 x 572 | ✓ |
| 3636 | 30.5 x 30.5 | 775 x 775 | ✓ |
| 4040 | 34.5 x 34.5 | 876 x 876 | ✓ |
| 4242 | 36.5 x 36.5 | 927 x 927 | ✓ |
| 5252 | 46.5 x 46.5 | 1181 x 1181 | ✓ |
| 6060 | 54.5 x 54.5 | 1384 x 1384 | ✓ |
| 6464 | 58.5 x 58.5 | 1486 x 1486 | ✓ |
| 7676 | 70.5 x 70.5 | 1791 x 1791 | ✓ |
| 8484 | 78.5 x 78.5 | 1994 x 1994 | ✓ |
| 100100 | 94.5 x 94.5 | 2400 x 2400 | ✓ |
Columbia will manufacture any size skylight in acrylic, in addition to those listed above, as a custom order. Custom size skylights are available in all acrylic glazing options at a premium price compared to standard sizes.