This standard specifies the general, physical, and magnetic requirements for interchangeability of the one - or two-sided, 5.25-Inch (130-mm) (nominal), 96-tracks-per-inch (tpi) (3,8-tracks-per-millimeter(tpmm)) flexible disk cartridge (for 7958-bits-per-radian(bpr) use) as required to achieve unformatted disk cartridge interchange among disk drives using 80 tracks per side and associated information processing systems. The two-sided flexible disk cartridge enclosed in a protective envelope and having two recording surfaces is of the type intended specifically for use with digital recording and reproducing equipment employing access mechanisms capable of positioning to these data tracks.