Compression
Compression level
  Here you can select the default compression level to be used. The maximum level will give the best compression ratio and the lowest will result in better compression speed. The default compression level is the recommended level by the plug-in and will often result in average compression ratio and speed.
 
Dictionary size
  Specify the default dictionary size to be used when compressing.
 
Recovery data
  Specify the default amount of recovery data to be mounted with the archive.
 
Other
  For information on the other compression settings please take a look here.