boonie hats, sometimes known as giggle hats, is a type of wide-brim hat generally used by Army & military forces. Usually, a fabric tape band of loops is sewn around the top of the hat. This 'foliage ring' is intended to hold added foliage as camouflage. The crown normally is vented with eyelets or small mesh panels. Snaps sometimes may also be provided with which to fix the brim like an Australian bush hat. boonie hats were first worn by the United States Army Forces in the Vietnam War, when U.S. Army Green Berets started wearing them in the field with Australian and Army of the Republic of Vietnam units. This type of hat is great for the sun & in hot weather.