Boonie hat A boonie hat , also known as a bush hat , is a form of wide - brim hat commonly used by military forces . Its design is similar to a bucket hat but with a stiffer brim . Often a fabric tape band of ' branch loops ' is sewn around the crown of the hat . This ' foliage ring ' is meant to hold additional vegetation as camouflage . A strap provides stability . The crown may be vented with rivets or mesh panels . Snaps may also be provided with which to fix the brim in the style of an Australian bush hat . U . S . military boonie hat . The boonie hat was introduced to the United States Armed Forces during the Vietnam War , when U . S . Army Green Berets began wearing them in the field , along with Australian and Army of the Republic of Vietnam units . These leopard spot or tigerstripe boonie hats were locally procured , the camo cloth was usually salvaged from other uniform items or with the former from a parachute or made up by the tailor . In 1967 , the U . S . Army began issuing boonie hats , as the " Hat , Jungle , with Insect Net " , made of cotton and wind - resistant poplin , in olive drab , tigerstripe , and ERDL pattern . It was meant to supplement and replace the patrol and baseball cap s that had been in service since World War II . As the U . S . military evolved away from a garrison mentality , the boonie found a permanent place as part of the uniform of all services . The boonie has changed little through the decades since the Vietnam War and was used in the Iraq War and still in the War in Afghanistan as an alternative to the patrol cap . The U . S . military boonie hat has come in a variety of camouflage patterns ; the current assortment includes U . S . M81 woodland , three - color desert , UCP , MultiCam , and both desert and woodland versions of MARPAT , as well as the Air Force ABU pattern . The boonie hat is often worn with the wearer ' s rank insignia pinned to the front , above the branch loops . Hat , Camouflage ( Tropical Combat ) Type II . In 1968 the U . S . Army authorized use of the woodland ERDL pattern ( Engineering Research Development Laboratory ) material , used in the 1969 and later production of hats in cotton ripstop material . These were labeled , " Hat , Camouflage ( Tropical Combat ) Type II " with contract dates starting in 1968 . They were in use from 1968 for both the Army and Air Force , and from 1969 - 70 for the Marine Corps and Navy . Hat , Sun , Hot Weather . Later boonies are called " Hat , Sun " or " Hat , Sun , Hot Weather " , which is still the designation for this type of cover . They are made in various patterns , in cotton ripstop or nylon blend cloth . Australian Army boonie hat . There is evidence that the Australian Army had been using wide - brimmed boonie hats , also known as giggle hats or bush hats , during the First and Second World War . However , the headgear was not very common among Australian troops , who mainly used the slouch hat s issued to nearly all Australian troops in the field . The bush hat gained popularity during the Malayan Emergency , in which protection from the searing heat of Malayan tropical conditions and the heavy rain that occurs regularly throughout Malaya proved to be necessary . Alongside the British , the Australian Army started issuing this type of hat , which had a steeper and shorter brim than its earlier counterparts . It was made with the same materials as the hot weather combat uniforms , unlike the slouch hat , which was beginning to take on a more ceremonial role rather than being field gear . These hats gained even more popularity during the Vietnam War , where they were called ' hats utility , jungle green ' , although they were colloquially known by the Australians as giggle hats or bush hats . During this conflict , nearly every Australian soldier was issued with the hat , mainly to protect soldiers from the elements . To ensure the latter , the army created several regulations : the hat was not allowed to be modified or cut whatsoever , and it had to be worn when outdoors at all times . The hat had also served the purpose of breaking up the recognizable outline of the soldier ' s head . It was made with cotton twill , and was issued in olive drab , the standard colour of Australian combat uniforms at the time . Current giggle hats are issued in Auscam and Desert Auscam . They continue to be heavily used by the Australian Defence Forces , and are issued to nearly every person serving in the ADF .