The Chrysler Building is considered a masterpiece of Art Deco architecture. The distinctive ornamentation of the building is based on features that were then being used on Chrysler automobiles. The corners of the 61st floor are graced with eagles, replicas of the 1929 Chrysler hood ornaments; on the 31st floor, the corner ornamentation are replicas of the 1929 Chrysler radiator caps. The building is constructed of masonry, with a steel frame, and metal cladding. In total, the building currently contains 3,862 windows on its facade and 4 banks of 8 elevators designed by the Otis Elevator Corporation. The building was declared a National Historic Landmark in 1976.