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.

GB103.12

Country / Post Great Britain
Date of Issue 31 May 2012
Primary theme National symbols (Flags)
Subject Post & Go - Union Flag
Width 55.0 mm
Height 24.0 mm
Denomination 1st class up to 100g
Number in set 1
Layout/Format self adhesive coil
Perforations 14 by 14
Stamp issuing authority Royal Mail of Great Britain
Printer De La Rue Security Print