Rucksack is a must-have tool for anyone working with archives. Open all popular archive formats including RAR, StuffIt, 7zip, and of course Zip. Safely backup your files with Rucksack's built-in encryption support. And convert easily between archive formats, such as from RAR to Zip.
Supported file formats
Zip
RAR (rar, r00, r01, r02, ...)[read only]
7zip (7z, 7z.001, 7z.002, ...)
Apple disk image (dmg)
Tar
Tar Gzip (tar.gz, tgz)
Tar Bzip2 (tar.bz2, tbz)
Tar Z (tar.Z)
CPIO (cpio)
ACE [read only]
ARJ [read only]
CAB [read only]
LhA (lha, lzh) [read only]
StuffIt (sit) [read only]
StuffIt Expander Archive (sea) [read only]
BinHex (hqx) [read only]
MacBinary (bin, macbin) [read only]
Linux RPM (rpm) [read only]
PAX [read only]
Amiga disk file (adf) [read only]
Compressed Amiga disk file (adz, ADZ) [read only]
Amiga DMS disk archive (dms, DMS) [read only]
Amiga LhF (f, F) [read only]
Amiga LZX (lzx) [read only]
Amiga DCS disk archive (dcs) [read only]
Amiga PackDev (pkd) [read only]
Amiga xMash disk archive (xms) [read only]
Amiga Zoom disk archive (zom) [read only]
HA archive [read only]

System Requirements
Rucksack runs on Mac OS X Leopard 10.5 and Snow Leopard 10.6