The black beret is a type of headgear. It is commonly worn by paramilitaries and militaries around the world, particularly armored forces such as the British Army's Royal Tank Regiment (RTR), the Royal Canadian Armoured Corps (RCAC), and the Royal Australian Armoured Corps (RAAC). Notable non-armored military units to wear the black beret include the Russian Naval Infantry (and formerly Soviet) and Russian OMON units, the United States Air Force (USAF) Tactical Air Control Party (TACP), Philippine National Police-Special Action Force (PNP-SAF) members, and the Royal Canadian Navy ("navy blue"). It was also worn by the United Kingdom's Royal Observer Corps (ROC) with their Royal Air Force (RAF) uniform, Metropolitan Manila Development Authority (MMDA).