We stock the following duct sizes:

3-1/4x10, 3-1/4x12, & 3-1/4x14 in 30" and 60" lengths

The following are available in 4 foot lengths

4x10 & 4x12

6x10, 6x12, & 6x14

7x10, 7x12, 7x14, 7x16, 7x18, & 7x20

8x10, 8x12, 8x14, 8x16, 8x20, & 8x24

10x20 & 10x25