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. (March 19, 2019). https://www.encyclopedia.com/computing/dictionaries-thesauruses-pictures-and-press-releases/disk-pack
"disk pack." A Dictionary of Computing. . Retrieved March 19, 2019 from Encyclopedia.com: https://www.encyclopedia.com/computing/dictionaries-thesauruses-pictures-and-press-releases/disk-pack