Bon Towarowy PeKaO checks were substitute legal tender (complementary currency) used in the People's Republic of Poland. The Polish government, needing hard foreign currency, introduced them in 1960. Citizens of Poland had to exchange foreign currency they had into these notes (bony in plural), issued by the government-controlled Bank Pekao. They were only accepted in special shops in Poland (Pewex, Baltona) where one could buy restricted, imported goods. Outside of Poland, bony had no value and were not regarded as legal tender.