The DryerJack Model DJK688 is a rather large galvanized roof cap, having a plate size of 14" x 14", with a hood size of 8" x 8" and about 8" high. The collar is 6 inches in diameter, a size that is typically found in commercial dryers or range hoods. There is no screen in this vent as it is assumed it is being used for clothes dryers. Unlike other roof vents, this lightweight damper is curved, which increases the efficiency dramatically. The opening is about 15% larger than the round pipe portion and with the curved damper, there is minimal restriction. The collar penetrates the plate about 3 inches and is sealed to the plate with a silicone bead. Note: Not recommended for use with a very high-profile roof tile like true Spanish Barrel as there is only 5 inches between the opening and the bottom plate. With the slope on the damper and the smooth surface, the vent/damper should make it difficult for a bird to build a nest. This vent is proudly made in the USA.