20 C. Merkur head, violet purple with overprint in type I, horizontal strip of three (! ! ! ) with only an overprint, in perfect condition unused, expertized Dr. Dub and photo expertize Lothar lift VP (2018) : "the condition is perfect. Unused postal stamps from public ownership with overprint in type I are extremely rare, there of the very small printing almost all stamps for franking purposes on covers were used there. "