In 1893, Belgium issued a new series of stamps showing a portrait of King Leopold II. The stamps have a pendant that reads: “Ne livrer le dimanche” and “Niet bestellen op zondag”. These are the so-called “Sunday stamps”, even though the text on the pendant means, that you cannot get mail delivered on Sundays. Todays stamp is the 2 franc issue with a CV of 75 $ for a mint copy.