Airmail, 1918, 6¢ orange, well centered amid large margins, tied by purple "Airmail Service Wash., N.Y., Phila., Washington, Dec 16, 1918" First Flight and Rate postmark on fresh cover with blue American Philatelic Society corner card, Very Fine and choice. Scott No. C1  $2,000. $0 (Image)

Airmail, 1918, 6¢ orange, o.g., never hinged, choice centering amid large evenly balanced margins, Extremely Fine to Superb. Scott No. C1  $140. $0 (Image)

Airmail, 1918, 6¢ orange, block of 4 with horizontal centerline, o.g., hinge remnant at top, never hinged at bottom, strong color, nicely centered throughout, Very Fine. Scott No. C1  $360. $0 (Image)