Processing of multiple files in OpenPGPBlackbox - SecureBlackbox®
Original PGP format can process (sign or encrypt or both) one data stream (file) and produce one PGP file as output. PGP Desktop version 9 introduced the feature of placing multiple files into one encrypted or signed PGP file. This is done by placing all files to TAR archive and then encrypting or signing this TAR archive.
OpenPGPBlackbox also can be used to put several files into one secure OpenPGP archive. And of course OpenPGPBlackbox can extract OpenPGP archives that contain multiple files inside.