2 inch by 11 inch opening. Gallery edition solid brass mail slot in an antique bronze finish with matching screws. Blends well with antique bronze, oil rubbed brass, aged bronze and venetian bronze hardware. Template on back of packaging for easier installation. V1911 series. Antique bronze solid brass mail slot. When uses in hollow doors use with Stanley National #1911s sleeve. Solid brass gives maximum corrosion resistance, Spring Action, lid seals out weather and dirt. The outside dimensions of the item including the plate are approximately 13-1/4 inches wide by 3-11/16 inches high. Product template is shown on the back of packaging for easy installation.