The shield contained within the Great Seal of the United States of America.
Note that when this is used as a separate symbol (rather than as part of the overall Great Seal), there are often white stars on the chief (upper band), as seen in File:US Senate Eagle and Shield gilded wood.jpg, File:Womans-Holy-War.jpg, File:Arms of the United States of America.jpg, File:CampCusterMI-HumanUSShield30000Men.jpg, File:Nebraska-TennisGirl-ca1905.jpg etc.
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