5 Kopecks

Vneshtorgbank's internal currency certificates were a controlled arbitrage mechanism, not general circulation money. The kopeck-denominated series issued from 1977 was designed for use at Beriozka ("birch tree") hard-currency shops — state retail outlets where Soviet citizens who received foreign earnings could spend them without the government losing access to hard currency. The kopeck fractionals were produced in distinct series distinguished by colored stripes, separating certificates earned through domestic foreign-currency wages from those received as remittances from abroad — a deliberate barrier to black-market convertibility.

Possession of these by ordinary Soviet citizens without a qualifying foreign-income source was technically illegal.