Duran Duran's 1983 7" single 'Union Of The Snake' (left) and bonus 7" flexi-disc. (photo: Pierre Oitmann) 

Duran Duran's 1983 single 'Union Of The Snake', as issued in Holland. Pictured left is the 7" vinyl single; right the "free" gift flexi-disc record, made out of plastic as thin as stationary paper. Flexi-discs were merely promotional tools, often used as give-aways with pop magazines in the mid-1980s. The sound quality of flexi-discs was rather poor, but, nevertheless, they've become quite collectible.