It looks to date to the late 1960's and could best be described as an exagerated trilby style.
Accented with two bands of green grosgrain ribbon with black topstitching, & finished off with two 3/4 inch buttons, black faux leather with brass rims.
This hat is in good vintage condition: one side of the brim is slightly flat due to storage.
Crown is 4 1/2" high, inner circumference: 20 1/2", which makes this a U.S. size 6 1/2 or a U.K. 6 3/8.
This would be great with an all black ensemble or mixed with other brights.