The World Association for the Development of Philately (WADP) and the Universal Postal Union (UPU) jointly conceived and developed the WADP Numbering System - WNS, which was launched on 1 January 2002.

BE039.04

Country / Post Belgium
Date of Issue 19 April 2004
Primary theme Fauna
Subject Nightingale
Width 24.0 mm
Height 27.66 mm
Denomination 0.01 €
Number in set 7 (show set)
Layout/Format sheet of 50
Perforations 11.5 by 11.5
Stamp issuing authority La Poste De Post Belgique
Printer La Poste Imprimerie du Timbre à Mechelen