Now showing: United States - Airmail stamps (1990 - 1999) - 9 stamps.
12. October WM: None Perforation: 11
27. April WM: None Perforation: 11
17. May WM: None Perforation: 11
21. June WM: None Perforation: 11
12. October WM: None Perforation: 11
13. July WM: None Perforation: 11¼
WM: None Perforation: Rouletted 11
30. July WM: None Perforation: Rouletted 11