20l. ultramarine (pos.67) with quadrille background (very intense), plate flaws identation of the bottom frame line and double lip, used. Very lagre margins all around, creased at upper left corner in margin the tip only, mentioned just for accuracy. The most prominent quadrille background ultramarine stamp we have seen from the Hellas 51f and 57 stamps so far. Superb quality and very rare. (Hellas 57aVa20F13/14).