Ridge Racers for Sony PSP was released on December 12, 2004 in Japan.
It was then released on November 17, 2005 as a PSP the Best edition [Model ULJS-19002], and then on the Japanese PlayStation Network on November 1, 2009 [Model UCKS-45053].
"Ridge Racer [Model ULUS-10001]
"Ridge Racer [Model UCES-00002]
[SK] "Ridge Racers [Model UCKS-45002]