File extension rzr is used by following file type(s):

File extension rzr file type description:
Renamed WinRAR archive

The RZR file extension is very uncommon file extension sometimes used for WinRAR archives, which otherwise have RAR file extension.

It is possible that the renamed file extension is associated with Razor 1911, a warez and demo group, with a history similar to that of Fairlight. According to the computer crime division of the United States Department of Justice, Razor 1911 is the "oldest game software piracy ring on the internet".

that open rzr files:
WinRAR (Microsoft Windows)