I think this cable is for an external SCSI Iomega Zip
drive. The Zip drive
has a DB25 connector on the back but it is a SCSI interface.  The drive is
at work and I am at home so I may be in error. 
        The SCSI ZIP drives we have all have the DB25 connector on
the ZIP end as well.  I've got an Iomega ZIP SCSI cable that I use
for connecting an old CMS SCSI hard disk up to my Mac Plus.
 I saw a SCSI to USB adapter in a catalog, I wonder how
good they are. 
        Isn't it actually going the other way, allowing you to
connect a SCSI device up to a USB connection?  I've got a 'Shuttle
Connection' cable, supplied by Philips with thier SCSI OMNIwriter
CD-RW, that allows it to be connected to a parallel printer port.
        Jeff
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