Combined Task Force (CTF) 115 was created to patrol the coastal waters of South Vietnam when it was discovered that North Vietnam was smuggling large amounts of weapons and materiel to Viet Cong forces in this south in civilian fishing vessels loaded in North Vietnam and then sailed south to rendezvous points in the South. The Navy established Operation Market Time (March 1965-1972) to prevent these North Vietnamese ships from supplying enemy forces in South Vietnam by sea. The Coastal Surveillance Force (Task Force 115) used a system of three barriers to patrol the South Vietnamese coast. The interdiction effort was extremely successful, and resulted in the North Vietnamese abandoning the coastal infiltration route in favor of the more secure "Ho Chi Minh Trail" through Laos and Cambodia. This small "beercan" insignia was made to be worn on the cap or beret and measures approximately 5cm in diameter. Scarce original.