This custom boonie hat was tailored from a US Marine Corps frog skin camouflage poncho, which came with a wide brimmed rainhat as well, though has a different design [1]. Custom hats made from rain ponchos like this one were often bought in Okinawa from local tailor shops after WW2 [2][3]. The material is coated with rubber on the inside for waterproofing and is intended to be reversible, though this feature is lost on this hat.
Sides:
Back:
Top:
Inside:
Hat has been worn as seen by wear and grime at the front due to sweat. The beach side camouflage print is visible on the inside.
Tag:
Size is printed onto the tag.
Vents:
Name:
Name stamped on headband of hat is probably for Major Frank Natt, who was in the Marines during the Korean and Vietnam Wars [4]. It is possible the 1st Lt. F. Natt at ASP-1 when it exploded on April 24, 1968 is the same individual since the rank is lower than Major [5].