The peso ley 18.188, usually known as either peso or, to distinguish it from the earlier peso moneda nacional, informally as peso ley, was the currency of Argentina between January 1, 1970 and May 5, 1983. It was subdivided into 100 centavo

Centavo

Centavo is a Spanish and Portuguese word, derived from the Latin centum, meaning "one hundred", and the suffix -avo, meaning "portion" or "fraction"...

s. Its symbol was $, sometimes $L. Its name comes from law 18188 which established it, effective April 5, 1969. Its ISO 4217

ISO 4217

ISO 4217 is a standard published by the International Standards Organization, which delineates currency designators, country codes , and references to minor units in three tables:* Table A.1 – Current currency & funds code list...

 code was ARL.
The peso ley replaced the peso moneda nacional

Argentine peso moneda nacional

The peso moneda nacional was the currency of Argentina between November 5, 1881 and December 31, 1969. It was subdivided into 100 centavos, with the argentino worth 5 pesos. Its symbol was m$n or $m/n. Its ISO 4217 code was ARM.-History:...

 at a rate of 100 to 1.