LH ARC (old version) compressed archive
ARC is a file extension for a compressed file used primarily by DOS. ARC stands for ARChive.
ARC files can contain either a Macintosh HFS archive, or an MS-DOS archive. No longer commonly used due to the outdated compression algorithms, there are many utilities that will open these files, including WinZip, and Macintosh Stuffit.
MIME type : application/arc, application/ArcMac