Collection: Square Roof Curbs (Non insulated) - 18 inch Tall

Diameter: 12"

Opening: 13"

Height 18"

L & W: 15"

Diameter: 14"

Opening: 15"

Height 18"

L & W: 17"

Diameter: 16"

Opening: 17"

Height 18"

L & W: 19"

Diameter: 18"

Opening: 19"

Height 18"

L & W: 21"

Diameter: 20"

Opening: 21"

Height 18"

L & W: 23"

Diameter: 24"

Opening: 25"

Height 18"

L & W: 27"

Diameter: 30"

Opening: 31"

Height 18"

L & W: 33"

Diameter: 36"

Opening: 37"

Height 18"

L & W: 39"

Diameter: 42"

Opening: 43"

Height 18"

L & W: 45"

Diameter: 48"

Opening: 49"

Height 18"

L & W: 51"