Blend air roof mounting plate for all Coleman Deluxe Blend Air units. Plate measures 15.5Ó x 15.5Ó with 9-3/4Ó ring for mounting crown. Mounts onto roof, box sticks inside attic. Box measures 8.5Ó x 5Ó x 5Ó deep. Round opening for connecting insulated duct. Open ends for exchange of attic air. Attic fan mounts in middle of plate.