Captain America's shield is a fictional item appearing in American comic books published by Marvel Comics. It is the primary defensive and offensive piece of equipment used by Captain America, and is intended to be an emblem of American culture. Over the years, Captain America has used several shields of varying composition and design. His original heater shield first appeared in Captain America Comics #1 (March 1941), published by Marvel's 1940s predecessor, Timely Comics. The circular shield best associated with the character debuted in the next issue, Captain America Comics #2. Original shield In his debut, Captain America (secretly U.S. Army Private Steve Rogers) is equipped with a heater-style shield made from steel. After complaints by rival comic-book publisher MLJ that the design was too similar to that of its own patriotic hero the Shield, Timely Comics replaced the triangular shield with a disc-shaped one. While the origin and fate of the original shield were not described in the original comics from the 1940s, the shield's fate was revealed decades later in 2001 through a retconned story. According to the tale, King T'Chaka of Wakanda met Captain America in early 1941 and gave him a sample of vibranium, an alien metal with unique vibration-absorption properties and found only in Wakanda and the Savage Land. The vibranium was used to make Captain America's circular shield, and his triangular one was retired. Captain America received a second triangular shield that he used until given his disc-shaped shield, presented to him by President Franklin Roosevelt. This second triangular shield was kept in storage with Rogers' other personal effects after the war. It was recovered at some point after Rogers joined the superhero team the Avengers in The Avengers #4, and was kept at Avengers Mansion. It was destroyed by the supervillain Mr. Hyde during a raid on the mansion by Baron Zemo's Masters of Evil, and later "plucked from time" and restored by Zemo in Thunderbolts #105 (October 2006). The shield (along with other sentimental items thought destroyed) was returned to Captain America. A third triangular shield is kept in the Smithsonian Institution. It was used by Captain America when he foiled a terrorist attack on the museum itself after the loss of his usual shield; it was then given to him in gratitude. This shield is destroyed several issues later by a Kree alien warrior. The shield destroyed by Hyde and restored