Souvenir set of (usually Russian) matchboxes with the souvenir label inserted into the transparent package. Matchboxes in a souvenir pack are stacked in one or two layers, fastened by a side tape and packed into cellophane. Some blocks were issued without souvenir labels, some even without a side tapes. Such souvenir pack is called "briquette" in Russian
Note: The first blocks in the USSR were issued in 1957 ("40 years of October" and "The Arms of the Soviet republics". They consisted of 16 matchboxes and a side tape); of the more rare sets should be noted the pack "The Hunters matches" (4 matchboxes + a side tape), produced by "Sibir" match factory in 1982. All known Russian souvenir packs was issued in the Soviet times.