Specifies the physical and magnetic characteristics. Also specifies the quality of the recorded signals, the recorded format and the recording method, thereby allowing data interchange between drives by means of such magnetic tape cartridges. Specifies two types of cartridges referred to as type A (magnetic tape of nominal thickness of 13 m and a nominal length of up to 60,5 m) and type B (magnetic tape of a nominal thickness of 9 m and a nominal length of up to 92,0 m).