Background Informations:
On January 21, 2010, China National Philatelic Corporation issued a four-piece set of first-day covers and a souvenir sheet cover, carrying a four-piece set of special stamps, "Site of Shanghai Expo", with a combined face value of 6.20yuan. The names of the stamps are "Expo Center" , "China Pavilion", "Performance Center" and "Theme Pavilion".