a maximum (codice_19 or) codice_20 for 24 bits with (256 or) 255 heads. in chs tuples specifying a geometry s actually means sectors per track, and where the (virtual) geometry still matches the capacity the disk contains codice_21 sectors. as larger hard disks have come into use, a cylinder has become also a logical disk structure, standardised at 16 065 sectors (codice_22).