These pay phones were used quite extensively in the USA by United Telephone/Carolina Telephone & Telegraph/Central Telephone (now collectively known as Sprint Local). Other independents used these as well. These were also used quite extensively in Canada.
Both rotary and Touch-Tone varieties exist. These phones can be found commonly in the following colors - brown, black, green and blue.
Versions made for the USA were made to be compatible with the Western Electric/AT&T dual-frequency tone ACTS system. Canadian versions originally used single tones but may have been later modified to use the dual-tone system.
Canadian versions could take either American or Canadian coins. I do not know if the USA version could take Canadian coins or not.
Most Centurions that are still in use in Sprint Local territory have been converted to COCOTs.
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