This is the very expensive ( USD 1,100 + ) 80 Pfennig Germania stamp,with Sarre overprint, CTO. The upper right corner has a fault ( At first glance one could get the impression that the corner has been torn apart and repasted.
Looking at it closer this is not very likely as the borders are without fault. It rather seems that its because the paper is slightly uneven). One cannot see very clearly but it seems that some fault exists.
So the price for this item is only 35 %of the catalog price. ( Michel DEM 2,500 ) Clean cover in fine condition.