Tile gap fillers fit into the spaces between the Shuttle's thermal protection tiles to close any narrow gaps. About the size of a bookmark but a bit thicker, the gap filler is a barrier that keeps heat from penetrating around the tiles. Gap fillers have black or white braided borders, according to their use between black or white tiles. They are made of a tough ceramic silica fiber strengthened with aluminum.
NASA gave this gap filler to the Museum after the Space Shuttle Columbia's first mission in 1981.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.