This 4 kopeck commemorative from the Soviet Union (1967) celebrates the 50th Anniversary of the Great October Socialist Revolution, featuring the state emblem of the Azerbaijan SSR set against the republic’s red-blue flag. Surrounding imagery includes oil derricks, Baku architecture, and revolutionary relief art, symbolizing Azerbaijan’s industrial and cultural identity within the USSR. Issued as part of a larger multi-republic series, this stamp is popular among collectors of Soviet federal issues, anniversary sets, and republic-emblem themes. Clean, bold design and strong historical significance make it a valued mid-century Soviet philatelic item.