1950's Air Mail from Finland to United States

Air mail cover from Helsinki to Milwaukee, Wisconsin, USA 29.1.1958. Letter rate to countries outside of Europe was 30 marks between 1.6.1956 and 31.3.1959. Air mail surcharge to United States was 17 marks for each 5 grams between 1.10.1957 and 31.3.1959. The cover below has a correct rate for an air mail letter of the third weight class (10-15 grams) (30 + 17*3 = 81). The cover does not have a readable arrival postmark.

Air mail cover from Helsinki to Milwaukee, Wisconsin, USA 12.5.1958. Letter rate to countries outside of Europe was 30 marks between 1.6.1956 and 31.3.1959. Air mail surcharge to United States was 17 marks for each 5 grams between 1.10.1957 and 31.3.1959. The cover below has a correct rate for an air mail letter of the third weight class (10-15 grams) (30 + 17*3 = 81). The cover does not have a readable arrival postmark.