Storage capacities ranged from 30 to 300 megabytes, over the range of track densities up to 400 tracks per inch, recording densities up to 6000 bits per inch, and pack sizes of 5 to 12 disks. Disk packs were introduced by IBM in 1963, and most types are subjects of international standards.
"disk pack." A Dictionary of Computing. . Encyclopedia.com. (August 19, 2018). http://www.encyclopedia.com/computing/dictionaries-thesauruses-pictures-and-press-releases/disk-pack
"disk pack." A Dictionary of Computing. . Retrieved August 19, 2018 from Encyclopedia.com: http://www.encyclopedia.com/computing/dictionaries-thesauruses-pictures-and-press-releases/disk-pack