A blurb on the piece from the Cooper-Hewitt website:
This installation commemorates the 75th anniversary of the 19th Amendment, which granted women the right to vote. The text of the monumental amendment was applied to the floor of the main waiting room in Grand Central Station, in eight-foot letters (9,276 point type).
And a note on the materials from the AIGA Design Archives:
Materials were partially donated by vendors. The letters were made from 3M's scotchguard floor graphics marking film.