Cut out dimensions: 21-1/8 inch on back, 19-9/16 centerline, 18-9/16 front edge (537mm X 497mm X 471mm).

Lid: 23-1/16 inch back, 21.5 inch centerline, 20-5/16 forward edge.

Hatch opening: 20 inches x 18 7/16 inches x 17 7/16 inches (508mm X 468mm X 443mm).

Flange: 22 3/4 inches x 21 3/16 inches x 20 3/16 inches (537mm X 497mm X 471mm)

Features anodized heavy-duty aluminum frames, vent, heavy-duty acrylic top, tie down dogs.

Other Bomar trapezoid hatch sizes are available, give us a call, toll free 877-932-7245 ext.116, Mon-Fri, 9-5 Pacific