This International Standard specifies the characteristics of 12,7 mm (0,5 in) wide magnetic tape with reel, to enable magnetic and mechanical interchangeability of such tape between information processing systems. This International Standard applies solely to magnetic tape for digital recording using the NRZ1 method of recording at 32 ftpmm and 356 ftpmm (800 ftpi and 9 042 ftpi) or the phase-encoded method of recording at 126 ftpmm (3 200 ftpi) in which the direction of magnetization is nominally longitudinal. NOTE 1 Some numeric values in the SI and/or Imperial measurement system in this International Standard have been rounded off and therefore are consistent with, but not exactly equal to, each other. Either system may be used, but the two should be neither intermixed nor reconverted. The original design was made using the Imperial measurement system.