Abstract: Cardboard blanks with fold lines between their panels are partially draped around arrays of cigarette packets in an apparatus wherein successive arrays which are being advanced along an elongated path at a first speed strip discrete blanks off a mouthpiece which is advanced along such path at a lesser second speed. Additional panels of a blank which is being transported by the mouthpiece, and a first panel of which is to be engaged and entrained by the front side of an oncoming array, are pivoted relative to the first panel along the respective fold lines by pivotable prefolding members which share the movement of and are caused to pivot relative to the mothpiece while the latter transports a blank at the second speed. The prefolding members cooperate with further folding members to pivot further panels of a blank relative to the additional panels while the blank is being transported by the mouthpiece.