A postcard issued by Historical Museum of Kotel (Котел). It shows the old Kotel carpet pattern with water-melon rinds. Thanks ceruleanmind.
It was sent inside an envelope with three other postcards. A pair of 1,00лв figurine stamps and a 0,40лв moth stamp were used. The postmarks of Pleven are faint, only able to recognize "12 IX" for its date.