The correct belt for Mirage with A/C has 6 ribs and a length of 1240mm.
Some makers offer a length of 1238mm which fits just as good. Any shorter and it becomes difficult to install.
Part number 6PK1238 or 6PK1240 (non metric: 488K6)
Our cars were made adhering to universal (metric) standards as harmonized by the International Standards Organization (ISO). In the last three remaining non-metric countries, namely Liberia, North Korea, and the USA, the 6PK1240 may be sold as 488K6. See bottom picture, where the belt has both printed on it.
Picture of the OEM belt 6PK1240 (Type 488K6 in some non-metric countries)