The sg3_utils package contains low level utilities for devices that use a SCSI
command set. Apart from SCSI parallel interface (SPI) devices, the SCSI
command set is used by ATAPI devices (CD/DVDs and tapes), USB mass storage
devices, Fibre Channel disks, IEEE 1394 storage devices (that use the "SBP" 
protocol), SAS, iSCSI and FCoE devices (amongst others).