Unified Vneshposyltorg checks were introduced in 1976 after the abolition of VPT certificates. They remained unchanged until 1992.
Vneshposyltorg checks (previously "certificates" and "bonds") were a kind of "parallel currency" that existed in the USSR in 1964–1988. They were used to pay salaries to Soviet citizens working abroad: mainly specialists employed under USSR construction contracts, as well as specialists (for example, teachers, doctors, and military advisers) working under contracts with foreign state and private institutions (hospitals, universities, etc.), rank-and-file embassy staff, and other persons within the USSR who received fees or transfers in foreign currency.
The main purpose of introducing the certificates, and later VPT checks, was the Soviet state's desire to limit foreign-currency wage expenditures for citizens working abroad (especially in capitalist countries, where otherwise employees would withdraw their entire salary in foreign currency and spend it all locally), and also to reduce the inflow into the country of private goods imports from uncontrolled sources. While staying abroad, part of the foreign-currency salary of overseas workers was voluntarily (but no more than 60%) transferred to an account at Vnesheconombank, from which, on the spot (usually through the economic adviser at the USSR Embassy) or upon returning to the USSR, one could receive a pre-ordered amount in the form of certificates (later, checks). Some categories of overseas employees of foreign trade organizations and diplomats could bring into the USSR a limited amount of foreign currency, which they were required to convert into certificates (checks) no later than the установленный deadline; otherwise, their possession of foreign currency was also considered illegal.