These are covers were sent to the USA. The rate for post cards was 45pf and letters 75pf. Usually they just used three 25pf stamps for a letter and 40pf and 5pf for the post cards, but on these people were somewhat of more creative.
The two above were sent after 3N1-20 were demonetized on October 31,1946.
Starting tomorrow I will post more covers going to a different country each day.