Scott Catalog # : 1912 - 1919 / Full Color Postal Commemorative Society First Day Covers.
Set Includes: 1912 Moon Walk / 1913 Space Shuttle Columbia Jettison of Boosters / 1914 Space Shuttle Columbia Releasing Satellite / 1915 Skylab / 1916 Pioneer 11, Saturn / 1917 Space Shuttle Columbia Lifting Off / 1918 Space Shuttle Columbia Landing and 1919 Hubble Telescope.