GCO12 Octagon Cedar Wood Gable Vent ~ Louver box 11.5 x 11.5 ~ Overall 15.5" x 15.5" ~ Kimball Designs Sanded Smooth Functional Ventilation Knot free Clear kiln dried Western Red Cedar Mitred joints, Exterior grade glue Aluminum Bug and Rodent Screen Louver Box: 11.5" x 11.5" x 3" Overall including trim: 15.5" x 15.5" x 3.75"