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.

SL045.04

Country / Post Sierra Leone
Date of Issue 10 May 2004
Primary theme Astronomy & Space (Astronauts & Cosmonauts)
Subject Yang Lewei orbits the Earth
Width 42.0 mm
Height 27.5 mm
Denomination 900 SLL
Number in set 12 (show set)
Layout/Format miniature sheet of 4 of 4 designs
Perforations 14 by 14
Stamp issuing authority Sierra Leone Postal Services Limited
Printer BDT International Security Printing Ltd