Files with RSF extension are associated with Mediafour’s MacDrive software tool for managing Macintosh-formatted hard drives on Windows systems. Applications that support RSF files allow users to access and use Apple devices, flash disks, CD and DVD discs, or hard drives formatted under Mac OS X (HFS, HFS+, and HFSX file system formats). MacDrive tools allow users to save, delete, format, or partition mounted disks.

RSF extension is also used for other types of files, for example, files used by LEGO robot design software.