check 7-zip.chm file
> Command Line Version
> Commands
> a [Add]
Tip:
Reminding,
7z commandline sometimes not flexible enough for some special cases....
Advice:
do not use Ultra Mode for big files,
Ultra Mode (Maximum Compression) is for special cases.......
Maximum Compression: It will take quite long time

and size gain is very low = not efficient
Default ( Normal ) compression is very efficient and get good enough compression with good speed.
Experiment yourself....
General Advice:
Development on computer and generally on engineering is about efficiency,
not about getting smallest size or maximum speed or .....
Ex:
It is not efficient to use fastest plane on public transport,
Public Plane Developers do not work on fastest plane but other things....
Something to Keep in mind on your plugin developments

