The Economic Union of Central African States is a monetary union of countries in Central Africa. Members (as of 2016) include Angola, Burundi, Cameroon, Central African Republic, Chad, Congo, Congo DR, Equatorial Guinea, Gabon, Sao Tome and Principe, and Rwanda.
In 1974, the "Central Bank of the Equatorial African States", which had issued six different coins during the 1960s and early 1970s, changed its name to "Bank of the Central African States."
(The flag used in the Coin Zoo is actually the African Union flag, of which all the countries of the Central African States are members.)
Central African States on Wikipedia