Naval hat of the early 18th century.  Measures about 12 inches and is out of Jack leather. Super early thick leather and would protect like a helmet from sword slashes.  The Sailors on American Ships wore these during the late 17th early 18th century.  I have bought and sold a few but none as nice as this with great age and two small holes in the crown for a badge of some type.  Super rare to find at all this is in untouched great condition. 
Condition: lots of age
Item 67