This is a postcard with pictures of the 1986 Finnish Christmas stamps. I found the following information on Stamp Collecting Blog.
In 1986 the Finnish Post issued their first, and so far also the last, se-tenant Christmas postage stamp issue. At the same time Christmas postage stamps returned back to use of two separate face values: discounted rate for early domestic mail and regular rate stamps for normal and international delivery.
I am participating in Sunday Stamps at Viridian's Postcard Blog