Defines the characteristics of 90 mm Optical Disk Cartridges (ODC) with a capacity of 2,3 GB per Cartridge. The Standard specifies only Type R/W for 2 048-byte sectors of such cartridge. Type R/W provides for data to be written, read and erased many times over the entire recording surface of the disk using the thermo-magnetic and magneto-optical effects. It is also referred to as "fully rewritable". This International Standard provides for 2 048-byte sectors only. All sectors on a disk are of the same size.