What type of hat is an 'Anthony Eden', a style popularised by the former British Prime Minister?

A homburg is a formal felt hat characterized by a single dent running down the center of the crown (called a "gutter crown"), a stiff brim shaped in a "kettle curl" and a bound edge trim.

An "Anthony Eden" hat, or simply an "Anthony Eden", was a silk-brimmed, black felt Homburg of the kind favoured in the 1930s by Anthony Eden, later 1st Earl of Avon (1897–1977). Eden was a Cabinet Minister in the British National Government, holding the offices of Lord Privy Seal from 1934–1935 and Foreign Secretary 1935 to 1938. He was later Dominions Secretary from 1939–1940, War Secretary in 1940, Foreign Secretary from 1940–1945 and 1951–1955, and Prime Minister 1955 to 1957.